Noted: inconsiderate

Why is it some people (generally teens/early 20's) don't really know how to act in public? This guy from the other day (who plays his music full blast) has friends who act just like him. If I sat down at a table...a cafe table where someone was already seated before me and saw they were studying, I would not sit next to them if I was in the mood to, say, hoot & holler, slap the table, shove my friends, and shout across the bloody room. No, I would go outside, or sit & talk quietly because that's the way my mother raised me. Should all their mother have been slapped in the mouth and sent to parenting classes? No, I doubt it. I am sure this is not their fault...or at least not all of them. These young men are old enough to take responsibility for their actions. When I was their age, I don't recall acting like a stupid animal.