>>542935908
It's not just MHA, it's the way the Japanese view the concept of a hero as a whole. Going out of your way to put on a costume and save people is just another 9 to 5 job that happens to be called being a Hero.
This is why Sonic NOT being a hero is so important to the way his character functions. Sonic doesn't clock in to do heroism, he doesn't get paid to do what he does, put on some memorable costume or take up some fancy nickname, or run with some hero organization. Sonic just helps people because he feels like it, because he's a kind person who hates shitheads like Eggman and decides to step in to "save the day" just because he happens to be in the area.
The whole concept is made by Jap creators for a Jap audience with Jap sensibilities, so it's no wonder why people overseas don't immediately understand unless they're already fans of Jap content.