Here's a good read on that:
Disinhibition is now being mentioned with some regularity in news articles as an explanation for how youth communicate differently when using the media of instant messaging, text messaging, and posting content on social networking sites. Because technology often provides 1) a perceived buffer from regular consequences and 2) a real buffer from traditional social cues, people will say and do things through technology that they would not do face-to-face. Youth who do not have any real understanding of the dangers or consequences of certain behavior will often talk openly about sexual issues or post provocative pictures online. While this may sometimes reflect their actual behavior, it is believed that many youth are being provocative in order to gain attention--not realizing the danger of some of their behaviors.
Although the para talks about it could be true for people of any age.