The Company did not travel breath-wise, for that would be ridiculous, taking into consideration Bombur's girth alone. Instead they travelled in two's and three's and it was a well-established system.

Kili and Fili took the lead as scouts. Thorin was well-aware of how he was consistently shoved near the middle, because according to others although they were heading for a mountain, which should have been a pretty distinct landmark, he was apt to getting lost. He denied such claims vehemently.
Balin and Ori led instead, and Gandalf usually joined them. Let them have it.

The true bulk of the dwarves took up the middle; first Bifur, Nori and Dori, the quietest of the Company, who stuck together and seldom spoke, then Gloin and Oin, who could scarce be tempted to be quiet.
Thorin himself walked with Dwalin most often, and Bombur and Bilbo brought up the rear, the slowest of all, with Bofur gently encouraging them on.

Thorin had no issue with Bombur, who was a fine, capable dwarf and a valuable asset to the Company, and he have kept a much quicker pace if he was so inclined; it was only the influence of Bilbo Baggins that was slowing him down.

Bilbo was absolutely dreadful at keeping pace; he was too curious, sidetracked by bland and mediocre scenery or enhanced by some flower like a common-elf.
His addition to the company was slowing them down- the rest of them would fire on ahead until Bilbo was almost lost on the previous horizon. Eventually someone would cry what would come to be an oft-repeated phrase,
"Where's Bilbo?"

And so they would wait, Thorin trying to hide his contempt, for the hobbit to scramble towards them, his apologies lingering in the air like a foul smell, "Oh I'm terribly sorry, you mustn't wait for me to catch up."
The other dwarves excused Bilbo's weakness easily, Bofur in particular.
"Ah sure, don't worry about it, we all could do with a rest anyway."
Thorin would signal for the group to leave as soon as Bilbo reached them, and gradually he would watch the hobbit fall behind all over again.

It was none of his concern. If Bilbo could not keep up, then let him fall so far behind that he would fall right back into the hobbit-hole from whence he came. Thorin had no pity for the weak.

It was perhaps the third or fourth night since Bilbo had joined them when Bofur approached him, asking for a word. Although it was regarding a trivial matter most like, a King was obliged to listen to the smallest concerns of his people, no matter how uninteresting.

The dwarves abused this informal doctrine of Thorin's regularly on the journey and sought him out just to ladle him with their worries and complaints, now that they had ample time to do so, safe in the knowledge that Thorin had nowhere else to escape to.
There wasn't enough food. The watch was too long. It was too cold.
None of them knew how Thorin longed to grab them by their beards and knock their heads together, and that was probably for the best.

Kili and Fili were the worst, taking advantage in a mocking way; with Kili asking Thorin would it ever be in his capacity to grow a full beard (the damnable lad had it cut short so not to impede on his archery) and Fili complaining that he would never be recognised as heir, with his blond locks so different to Thorin's and Kili's, (as if mere aesthetics would be enough to deny a prince his dues.)

Thorin understood that a true King needed to be patient, but he also knew that there was a line, and Kili and Fili had crossed it, and so a system was put in place- if either of them had concerns, they brought them to Balin first, who judged if they were of import or not. This worked well as a way to chasten his sister-sons, but Thorin knew that it would be condescending to ask any other dwarf to do the same. So he bore their burdens, albeit unwillingly.

It was then with great apprehension that he stood up to talk with Bofur. He had managed to secure a place in close proximity to the fire, and knew it would not be there on his return. He may have been a King, but he did not expect better treatment, and knew he would not find it even he did.

They walked a short distance, silence heavy between them, the murmurs of the others fading. Thorin had never spoken much with the toy-maker, and Bofur had so far proved himself not to be the type to complain, which Thorin approved of.

Bofur spoke then, quietly.
"Ah Thorin, not meaning any disrespect to you, but can't you see what you're doing to poor Bilbo?"

Oh it was regarding the burglar. Yes, poor Bilbo. If some of the Company had their way, they would all spend the journey crying on the behalf of the hobbit, and bundle him up and carry him to the mountain themselves.
Thorin was not so easily moved.

"Out with it. What is your concern?"

Bofur squirmed a little under Thorin's glare.

"Well it's just- well he's half the size of us, isn't he? It's hardly far to ask him to keep up from the back- look at the length of his legs compared to ours! He's running flat-out as it is!"

Thorin glanced discreetly at Bilbo, who was some distance away yet illuminated by the light of the fire. His legs did seem quite short now that it was mentioned, yet Thorin noted his feet were of decent size at least.

"What would you have me do?" he asked Bofur, because a King should listen to his men, and Bofur did seem opinionated on the matter.

Bofur paused for a moment, as if afraid that Thorin was only mocking him, and then cautiously continued.
"Well see if we put him nearer to the front, he wouldn't fall behind as easily. And then, you know, we could have a rear-guard instead of..."
He trailed off, perhaps wondering if he'd gone too far.

Thorin remained silent for some time before clasping Bofur's shoulder. "It will be done."

Kili and Fili had no issue with the hobbit, so the next morning Thorin moved Bilbo up to the front to scout ahead with them.
It was disastrous as could be expected. Bilbo was even worse than his sister-sons at judging what was note-worthy and what was not.
Sometimes, he would run back with entirely useless information such as, "the trees will gradually change from oaks to ash". Bilbo had an Elvish affinity for plants, which Thorin found it disgusting.

Balin at least was surprisingly patient with the hobbit, and gently tried to teach him about scouting.
"See laddie, the kind of thing we need to know is are orcs up ahead, or imminent danger of some sort. The rest we can figure out for ourselves."

He said it kindly, but Bilbo was no fool. He fell back after only one morning of scouting. Balin then had the audacity to look at Thorin in a disapproving matter, as if to say, the front is no place for a hobbit, what were you thinking?

Gandalf and Ori on the other hand, had been greatly amused by the hobbit's tidbits of information and would have gladly let Bilbo stay scouting, if only for entertainment's sake. When Thorin questioned Gandalf as to why the quantity of daisies ahead was so fascinating to him, the wizard only tilted his head and murmured that the smallest detail could make the biggest difference.
Wizards could be nearly more infuriating than hobbits in matters like this.

(Thorin spent an entire afternoon contemplating the tactical advantages, if any, of knowing how many flowers lay ahead. Daisies weren't even edible, for Mahal's sake. It was a good afternoon wasted.)

And so, encouraged by Balin, Thorin let the damned hobbit march in the middle, where he couldn't possibly get lost or left behind.
Bilbo eyed up Bifur, with the axe in his head, and Dwalin, with his tattoos, and muttered something quietly about preferring to stay where he was, thanks. No one paid him any heed.

Thorin sincerely hoped that that would be the end of the matter.