Thank you for your comment, Doug.
I did hear about the promiscuity issue in that environment. Unfortunately, it affects the straight realm as well. Replace "guys" by "girls" in your passage about bragging, and this will sound quite common as well.
I agree with you that public demonstration of physiological processes is not nice, irrespective of sexual orientation. Also an excessively provoking behaviour raises doubts whether those people are true, the same as football fans are hardly real amateurs of football. Pity it casts a shadow on the whole group.