I think as long as the rules aren't broken, then it would be impossible to prove someone is a catfish, unless they use photographs "borrowed" from the internet. Even then, one or two GAGers openly state the photo is not of themselves.
When it comes down to it, so what if someone is 60 instead of 16. So what if they're male instead of female. It's how they apply themselves to the questions and takes on GAG that matters. If they stick to the rules, there's not much harm done.
Well... I think there should be some identification requirements to prove who you are but on gag? Nah. I mean have the people here are trolls anyway. I don't think it's going to hurt anyone. But if someone had stolen another's identity and was doing something illegal on here? Yeah, I think serious action should be taken. You have to accept you can't really censor the internet or do much unless you can prove the law is being violated.
It would be too much an effort to find out if they are truthfully catfishing. The admins generally can't handle their responsibilities on this website as it is. They would never make an effort for that.
That'd be a difficult thing to do. How can you be so sure that someone is a catfish at times? It's obviously not approved/looked down upon for users to do, but those people could just create a new account over and over again.