I don't like carrying cash, and if I do, it's usually less than $20. If I see a funny beggar sign, or I'm stuck at a light, I'll toss them my cash/change. Though if I'm harassed by a homeless person, including the shit stick who wants to clean my windshield, or some dick head pretending to beg for gas (but won't let you fill up their tank, they want the $20) I will straight tell them to fuck off and go somewhere else. The window cleaners especially annoy the fuck out of me. Don't put your grimy, shitty shit on my car, I just washed it you stupid fuck.
I had one guy asking for gas, I said I'd give the teller $20 on #2, guy freaked out with joy - only time I've done that. Every other time they've gotten enraged when I wouldn't just give them the cash. Uh, fuck you, I don't carry cash yiu fuckin hippy.
I'll do the same for homeless with my fries, since I never eat them. "Here you go." They always look so damned happy.
In Austin they're usually pretty passive, old crazy folks with disabilities and a starving dog, unless you encounter them outside your vehicle... Save Mopac, where, North of 45th, you encounter the window washers that I want to run over near Anderson Lane. They'll also try to sell you gas station roses, like wtf, I don't smoke crack, get the fuck off the road and out of my way.