You do your best to avoid them because it always feels a little bad to say know since you don't really know their situation, but we tell ourselves the money is just going to go to booze or drugs if we give it to them.
I had a teacher who used to keep a box of granola bars in their car to give to bums instead of money, you can't buy booze or drugs with a snack.
My mom's father in law is a bum now , well homeless ( again ) I should say since he's always been a bum.
His last work was as a carnie a few years ago, if you saw him walking done the street on a good day you could still tell he's a bum.
There's no way to tell the how and why someone has gotten to the point that you see them. It could be legitimate (down-on-their-luck, medical insurance broke, etc) or a scam ("professional" bums who live off of the bleeding hearts of average people). I don't give money to anyone - not even friends lol - because you can't know where that money is going to end up. I don't want to be empowering someones addiction.
I try to help people when I can. If I witness a car wreck I stop and help. If I see a car fire I'll pull out my extinguisher. If someone's bleeding I pull out my first aid kit. But if someone walks up to me out of the blue asking for money I tell them no.
It's also why I hate taxes. You give your money to the state, because they say it'll go to fix the roads (a common lie). And then it goes to protect illegals or paint rainbows in the streets or whatever. The government should announce the needs it has, and then people who can help and want to help can do what they can to fill that need. I'm tired of just giving them money and the roads just get worse and crime gets worse and there's more homeless on the streets.