When i see a homeless person begging, if i have food mostly fruit i give it, rarely i have half a sandwich which I'll offer but i'll explain its not been eaten, even doggy bags ive taken home unless it's something i really wanna eat.
But i often dont have change and will say "im sorry but i don't have change"

When people are handing out flyers or newspapers that i don't want i look at them and say "no, thank you" and keep it moving.

Maybe you could try doing that. They will be hurt regardless because they're in need but as you say some courtesy wouldn't do anyone any harm.

I am not human, but I see you are human.

This is the advice for human.

If you are in the ruler place of the society, you should be ashamed of yourself.
If you are the mid class, mind your own business, do whatever you need.
If you yourself live a bad life, you should gather them, teach them how to live a proper life instead of begging, teach them how to steal, rob, kill and never get caught, live like every noble man should be.

Flaws bubble up all the time.