Usually when I lived in Philly I'd let the homeless have my leftovers after dinner. Had to walk a lot around downtown (no car then), and never had a problem. Of course, it was usually late at night (which means COLD) and these guys are huddled into doorways. I figure the truly homeless could use a good meal. I also figure A) I've got my Cold steel with me, and B) if they're under-nourished, I should be able to run fast enough to get away.

Big city bums get nothing from me (hahaha... I guess Philly isn't a big city?) during the day. We had one couple in West L.A. that, rumor had it, earned enough panhandling off college kids to afford their house.