And maybe the physical thing you provide to that person may only last for an hour, but the memory of something a kind person did for them will (hopefully) persist as well
I don’t know if you have been in India but I have. Begging has become a profession there. So most likely they won’t recognize individual donors. Also what OP mentioned is a real problem. Easily you’ll meet more than 20 homeless people at once around you in any big railway station.
From what I understand, shitty politics and rising inequality is the reason behind this.