What is the deal with the movie ratings system?

I am 16 years old and my friend is 17 years old. We recently went to see American Gangster, an R-rated film. My friend purchased both the tickets, in accordance to the law, yet about 15 minutes into the movie, the manager asked to see my ID. After informing the manager I was with my friend who was of the age to view an R-rated film, who purchased my ticket, I was asked to leave the film. I simply informed the manager that I abided by the only age-restriction that was on the front window? Morally and legally, do I have any case in not being only upset, but embarrassed in my own town's movie theatre?

What is the deal with the movie ratings system?the grand theater

It sucks but no you have no case. The person you are with has to be a guardian type.

That's the way it stands now. I am not aware that the system has been tested in the courts. If you want you can try legal redress but it will cost you.

What is the deal with the movie ratings system?soap opera opera theater

You don't have a case. It sucks that you were embarrassed in the theatre, but you weren't there with a guardian or parent. Thus, you were violating the rules/laws about it. And most signs in front of theatres say that you "Must be accompanied by a parent or guardian...", not "You can see the movie if your obviously 17 year-old friend, who could not possibly be your parent or guardian, bought you a ticket."

It's irksome, yes, but that's how it is. You only have one more year to wait, though.
WTF is with ALL the movies being rated R?! Like seriously. All of the movies that look really good are R-rated. It's f*ing gay man.
"restricted unless parent or guardian"

your friend is neither. sorry.
I am sixteen as well and I would be pissed. That's so gay man, you do have a right to be upset.