Found $3

My boyfriend and I went to Dunkin Donuts this morning because he likes his coffee. And, of course, I can't resist their breakfast sandwiches and hash browns. While he was paying for his breakfast, I some folded up dollar bills by his foot. I picked them up and asked them if he dropped them, but he hadn't. It was 3 dollars. And I felt guilty, but I wasn't about to ask a room full of people if they had dropped cash. Anyone could have claimed it. So basically I got my egg sandwich for 50 cents.

I rarely find money and I always feel guilty about keeping it. If it had been a lot more, I would have tried to find the person who dropped it. What do other people do in this situation?