Altcoins, who owns the amount of coins?

Hi, Im quite new to the cryptoworld so excuse me if I'm totally off with my questions in this post.
I'm wondering tho. The power of cryptocurrency is for a part the deviation of money around the world. No banks who have it all or most of it. But who creates these altcoins? Isnt it possible that in some altcoins, half of the total supply are in the hands of the creators?