It is unfortunately very true that some people delight in putting others down. For some reason it gives them a sense of superiority.
Drug addicts typically take drugs not to feel better, but to feel less bad. I think it is the same for these people; they put other people down to feel less shitty about themselves. I agree with you, the right course of action is to let them be miserable and focus on people who can be positive with you. Day to day is hard enough as it is!
I think you hit the nail on the head there! Often people seem to be doing it to feel better about themselves, but I'm not sure it's a good solution for that lol. Thanks for stopping by and commenting!