There are panhandlers at every grocery store and many corners. It's really a lot. If you feel like helping, do this.
After you have completed your shopping trip, but one refrigerated bottle of water, store brand or generic.
As your pulling out of the lot, give them the refrigerated water. Where I live water is so important and many homeless don't carry any.
They are very grateful, and you don't have to worry that the money you gave them will go to drugs, alcohol or cigarettes!