The internet creates big pockets of social groups that have no consideration of age, race, social status, etc. There's an interesting side-effect of looking for validation from your peers when you don't know what those people are actually like. We can act more mature by looking up to a mature audience, we can look down on a less mature audience, or we can resonate with the values of a less mature audience. I went from Digg to reddit to HN mainly due to interests/content, but also because I looked up to the more mature audiences. Some people will stick to platforms where they are entertained by immaturity and seek those people's validation by mimicking them.