Korean Etiquette...?

I've been moved to the bigger gyomoshil (big office with all the teacher's desks) which houses the bulk of the teachers, about 30-40 teachers are in this room alone. There are rows of desks, about 3 desks in each row that are pushed right next to each other. So basically one long row of desks split into thirds. Each row is butting up against another row with the desks facing the other row, except there are these shelves that block you from seeing the teacher across from you. Um, hope that makes sense. I wish I could take a picture of my gyomoshil but I feel like it'd freak out the other teachers. Or make them think I was weirder than they already do.

Anyway, one major problem with sitting in the main office is that I never know what to do with my food. In Korea, sharing food is major. It's part of how you establish friendships and relationships with people. However, with 30-40 other teachers, sharing your food with everyone else in the room isn't exactly ideal. Nor is it expected. But it seems to be polite (and expected?) to offer whatever you're eating to the teachers sitting near you. The other teachers around me have already offered me food on several occasions so now I feel I must offer as well. The only problem is that sometimes I dont want to, or I'm eating something that's not exactly easy to share, like a cereal bar or something.

I don't want to make it sound like I mind sharing my food, because most of the time I really don't mind. But now that I've started working out everyday afterschool (more on that later), I need to eat food before I workout. I also tend to eat dinner late and I've noticed that I've been feeling very lightheaded after my workouts, probably because I'm not eating enough during the day to warrant exercising. I also have a stash of food in my desk now which I feel like I should share but then if I do that, I'll hardly have any left. On the other hand, is it rude to be eating all this food by myself? Sigh. Also, I rarely eat breakfast in the morning but then of course, I'm starving by 10:00. So I might go and buy a snack somewhere, usually a pastry, and I usually don't share that because it's my breakfast! And I'm just too hungry. And it's usually small anyway, barely enough to fill me up. Is that selfish of me? Probably.

I'm also buying all this food with my money, as opposed to bringing stuff from home because my host mom never buys snacks so there's no food to bring. So I do kind of want to make it last because I'm definitely not raking in the money here. And God do I have to spend money just for work alone--bus transportation, snacks, coffee, lunch fee, supplies, etc. etc.

Even though I'm clearly worried about this, the other teachers have been quite understanding. I guess maybe they understand that as an American, I might not be used to always sharing my food. But I do feel weird when I'm eating something and everyone around me can see me eating and I always wonder if I should offer or not. It's something I'm constantly worrying about and sometimes feel guilty about. It sounds silly (and to some extent, it is silly) but it's also a perfect example of the constant uncertainty, the constant doubt and worry you experience as a foreigner living abroad.