TBH, if I were homeless I don't think I'd trust food from random strangers, especially some 13 year old kids who may be trying to pull some prank by slipping something into the food for a laugh. There are soup kitchens, shelters, food pantries, etc., that have food for the homeless and poor.
We had a social worker come in to do an assembly at my high school when I growing up. He brought in a few homeless people from our city to speak to our class. It was extremely eye-opening. They explained that a lot of them wanted to be homeless and preferred that lifestyle for a variety of reasons - freedom to do what they wanted, a lower-stress lifestyle, not wanting to pay taxes, etc. That was kind of a shocker to me - who would want to be homeless? But for a variety of different reasons, people do choose to be.
I think there are those who are handicap, mentally especially, who are in bad situations and need help and are not homeless by choice. But there's also such a vast array of resources available, there's no reason you should be out on the street if you're not in that particular niche - there are homeless shelters, soup kitchens, etc, like you mentioned. Heck, even if you go to jail, at least you get 3 meals a day and a sheltered place to sleep in, not to mention cable TV.
I'm all for helping the poor, but I like the idea of buying them food more than simply giving them money. My high school gym teacher always said to check their fingernails when they held out their hands - if they were dirty, then they were really homeless, if they were clean, they were panhandling for moola and were okay otherwise. I like the concept of educating or training people, or having them do work, in return for food and other things, rather than just handing out freebies - the "teach a man to fish" bit.