Its an interesting topic. The way I see it is...the reason why there are more males who are into MLP is kinda because...that's just how we guys are. Have you ever noticed that when a group of guys likes something, we become absolutley obsessed with it? Not saying girls can't be like that too, but (and I'm no pchycologist) guys just seem to be way more vehement when it comes to liking things, or fads, etc. MLP is one of the cases. I got into because its a great show, it makes me laugh, and I really like it. I'm sure its the same for anyone, girl or boy. But as for the reason there are more guys? Honestly that's just how we are. If its good, and if other guys like it, we make it into a frat party, so to speak.
Does that make sense? I hope so cause I don't want to use that much brain power to write a responce again.