I ditto the pancake idea. If someone has an electric griddle you can borrow (or if you have one) take it! You can whip up tons of pancakes in a hurry (use Pam spray!). I add mashed ripe bananas to my pancakes and a splash of vanilla extract...and people go crazy about them! Cook lots of bacon, too, to serve on the side.
If you're feeding that many people...you'll have to spend a little money. Others are spending the same on lunch and dinner, right? I would think those who have the dinner task are spending way more money.
Also...don't know if you have access to an oven. But monkey bread is VERY cheap (just 3 biscuit dough tubes/cinnamon sugar/butter/brown sugar)...but it's just a breakfast bread. I usually serve an egg casserole with it.