What kind of mentality is it to see jokes?

Watching the fire from the other side, saying something unpleasant, huh? Gloat over the misfortunes of others.

This is a normal phenomenon that ordinary people can't control. They met unhappy things. If others encounter worse things, their hearts will be very balanced and their bad emotions will be adjusted (uncontrolled).

Painful people need more painful people to comfort them?

You can also understand it as "conservation of mass". Some people are sad, and naturally some people are happy.