Food is significant in The Hobbit because it is used as a sign of friendship, and it is a motivation for violent behavior in enemies.
There are two aspects of food. First, it can be shared with friends. Second, those who want to make you food are your enemies.
When the dwarves first gather, they share a meal. This is an important aspect of the beginning of their journey and establishes them in Bilbo’s debt. His hospitality, intentional or not, is what starts the journey.
So after that the party went along very merrily, and they told stories or sang songs as they rode forward all day, except of course when they stopped for meals. (ch 2)
Even though Bilbo can’t eat as much as he likes, the fact that there is food and they can share it together helps him get to know the other adventurers better and appreciate the journey more.
Another aspect of food is that sometimes creatures want to make them food. The first example is the trolls, who steal their horses and then try to eat them. Then of course there is Gollum, who agrees not to eat Bilbo if he can win the riddle game. The wargs and spiders also want to make them food.