This definitely shouldn't have received an R rating.

They only used the F-word 9 times (all in a non-sexual context), and they had 2 or 3 brief shots of characters smoking pot. I don't think that should warrant an R rating. If you use it more than 15 times in a non-sexual context, then the film should receive an R rating. And if you can smoke cigarettes in a PG-13-rated movie, then you should be able to smoke pot (which is legal in certain regions of the country) in a PG-13 rated movie.

This is what it should've been rated:

PG-13 for brief strong language, drug use, some sexual references & thematic elements

The MPAA is extremely flawed. It must be fixed. This definitely should've been PG-13, not R.