I think it's because theres a lot of mistrust towards beggars. Some people wont give them money because they're sure the beggar is just gonna spend it on drugs and alcohol and some dont help because they think the beggar is someone pretending to be homeless to get free money.
Theres a lot of reasons why people dont offer money, but in the end, it's their money and they can choose how they please to spend it
At least here in my city I rarely trust on beggars because it's kind of easy to buy drugs since it's a state (county) close to the border and close to Tamaulipas.
Life tip: many shops offer shelter ticket books for the area, get a booklet and if they ask money for the shelter, give them a direct ticket for it. They do need their name on their ticket and an ID, but they wouldn't have been let in otherwise either so it confirms the legitimacy of their request. Or offer to buy them food instead, many will be happy to walk with you to do so or wait for you outside the shop.
Then you also get thr guys that directly tell you: "no man, I want the money."
Theres a lot of reasons why people dont offer money, but in the end, it's their money and they can choose how they please to spend it
Then you also get thr guys that directly tell you: "no man, I want the money."