Several people have already raised concerns with the fact that they got banned from several unrelated .ml communities by the same mod for breaking the rules in one community. There are several topics with broad appeal that have their largest community on .ml. Switching instances is basically the same as making another account because you're still subject to the .ml moderation.
The people don't really do that. A move needs to start from the mods, whether it's because they want to move or because they did something to piss everybody off.