I will admit I judged some parents harshly today. My husband and I went to see "Bad Grandpa". There were four different families that brought children 4/5 years of age. I'm no prude, believe you me, but I could not believe they subjected their kids to that content. The movie was hilarious, but not appropriate for young kids at all.
ETA: I don't think all R- rated movies are wholly inappropriate, but there is no question that "Bad Grandpa" is. It was created by the same people who made "Jackass" for goodness sakes. I haven't laughed that hard in a while, BUT it was NO place for a child.