I don't know why I'm still sometimes boggled by this kind of behavior, probably because it has never made sense to me.
I just read a line from Rolling Stone in an article about Trump to the effect that "America is trending stupid", and to that I will add "and rude". Bad parenting, the ME generation, narcissistic sense of entitlement, all the new normal for a lot of the population. Still some great people in the world though so don't let it bug you too much, and don't let it make you want to paint everyone with the same brush.
I gave a street beggar my new $20 cap last week to keep the sun off her head, she was so very grateful. The next day she wasn't wearing it when I drove by in my 1997 beater, and was still out in the hot sun bare headed, I guess to earn more hats. Ah, well, the point was that I did something I felt good about. That's the reward.
I try to be polite, and if someone gives me something, I say thank you. I'm always surprised how some people treat waiters and waitresses so disrespectfully. As far as people like Trump, I have to wonder when not having a filter, rudely saying whatever comes to mind with no thought, and spewing vitriol all over the place, became an admirable trait in someone. So many people say, "he tells it like it is", but being obnoxious, rude, and condescending is not the same as telling it like it is.
I quote Teek, because I have some experience dealing with people like the beggar, and in all likelihood, she lost the hat ten minutes after she got it, or someone stole it from her. I doubt that she is trying to get hats. People like that find themselves in those circumstances for a reason, and it is because they can not function well. It is a mental illness, and hanging on to something, a hat, is an accomplishment that is beyond their mental capabilities. Give her another one, and the same thing will happen.
For me, if I give someone something, I don't expect much. I figure that either I didn't want it around, cluttering up my life, or I figure that they needed it more than I did. Either way, I wanted to get rid of it, and so I gave it away. I think that it is nice when people are polite and thoughtful, and when they take the time to thank me, or get back to me, but I don't expect that. So if someone is thoughtful toward me, that is sugar. But that is just me. I know that a lot of people want a return, even if it is just a smile, and that is fine and that it is not unreasonable. But that is just how I feel, not how I think others should feel.