With Troy, everything good in his life can be described with baked goods and pastries.
His friendship with Abed is a giant cookie. It's huge, strange, weird and very unexpected. Still, it works. No one questions a giant cookie. It's just a cookie. But giant.
His relationship with Britta is like finding a box of mixed doughnuts. She's the mysterious one, and he doesn't know just from looking at her what's inside her. She's got a lot of crazy, so he really doesn't understand her. But he wants to be along for the ride when he's not with his BFF Abed.
So if he yelled at Jeff for trying all the doughnuts, well, that's because to him it makes sense. Britta is a sweet mystery, and Jeff shouldn't get to have all the good things first. Troy deserves good things, too. Like Abed. Or Britta.