This could have also been called War games ... there are certain things that I don't fully understand. One of those being how males act around each other or how and what they do to each other ... thinking they are funny or whatever.
Now there is an explanation ... of sorts, at the beginning of the movie. One of the better moments one may think ... or not so much. It is tough to know what will or won't really land with anyone watching. I thought the meal with the parent was funny akward ... even if quite on the nose with the euphism ... literally explaining the joke to the audience. And it still worked, because of the actors delivering on their part.
Having said that, I never really fully got behind the buddy games myself. Again, might be different for other people watching and testicle rubbing or other gross "jokes" might land exactly where intended or go over your head - pun very much intended.
There are some genuine funny moments and I don't usually vote movies badly, based on their profanity ... if you do, you probably shouldn't watch this in the first place though. I checked if this movie was one of the cases where there is an unrated version along the theatrical ... but the theatrical one seems to go all the way already. Again, humor and fun can only be defined by oneself ... and therefor me saying this misses a lot of its shots either means something to you or it doesn't ... I have seen way worse of course.