My general experience is that people asking for money don't need it, not in the sense they'd starve without it anyway.

In the UK people asking for money straight out are usually drinkers. Drug users and scammers tend to want more than loose change hence the more elaborate stories.

I should add that I have been homeless and without money. One time my only option of eating was stealing food or asking for money. I chose not to eat.

I could walk you round a city in the UK and I could point out the real homeless and desperate people that you would never see - mainly because these are not the people asking for money.

I appreciate there is a huge difference here between UK and US since we have a welfare system that is many times more generous than yours. The people you encounter may indeed need the money?