While I can understand the questions you are asking about the film, I feel like asking these questions sucks all the fun out of it. I mean, they are animated movies. Cartoons. For kids. You really think little kids are sitting there thinking "but why isn't the government getting involved to try and discover the source of this magic?!?!". No, probably not. I wasn't even thinking that, and I'm 21. I just want to watch and enjoy the movie. Not everything can make sense in a show about talking ponies.
On top of that, the EG world, while yes they appear human and don't have access to magic like the ponies in Equestria, they have all different wacky colored skin and hair, not to mention names that are not human. My point being, this "human" world is completely different from the real world to begin with. I mean really, all this is like asking "why does no one find it weird that Brian the dog can talk?" about Family Guy. At the end of the day it's just a cartoon, and so I sit back and enjoy