[quote=@Grimhildr]
i honestly don't get why it needs to be in the gm's separate rules, or the forum rules at all. isn't it common sense to know that a gm can accept and deny whoever they want, for whatever reasons? ¯\_(ツ)_/¯
[/quote]

This.

It's their fucking thread, therefor they make the rules and have the final say. I don't know why anyone would feel like they couldn't do this; I've never hesitated to deny someone. Opinions are always welcome yeah, but they are just that; Opinions. The GM is the one who's supposed to watch over the damn thing and make sure it runs smoothly; They don't get that by going "lol iunno" and letting people do whatever they want. 

Otherwise roleplays would be a [b]complete[/b] mess. I can't believe of all things this is an issue people are having. I'm shaking my head ashamed.