The internet doesn't draw in anyone particular type of people, at least in this day and age. Everyone uses the internet, and I'd put some money on a bet that it's pretty even amongst the general population.
Anyway, the internet grants people good old fashioned immunity for the stupid and idiotic things they spew forth. This generally serves to maginfy a person's inner "whatever" that they can't do "in real life".
So, if you're a god fearing individual, for example, you fall into two groups. The first gets on the internet and probably look at porn, and spends time on forums talking about your faith, and the aspects of it that don't make much sense or that you have doubts about.
You're free from the judging eyes of others of your faith whom you perceive to judge you for your actions.
The second gets on the internet and uses it as a soap box. They come across as rude, ignorant, and insultingly dense.
Athiests, I find, are divided very clearly into two groups. Those who don't believe in God, and are happy to talk about it. And those who hate religion, and spew their bullshit all over everything and anyone they come across.
The first group are the normal members of the public. If they didn't tell you they didn't believe in God, you'd never know the difference. They are good, honest, hard working people who simply get by just like those who believe in God.
The second group are the idiots. They think that not believing in God makes them "more logical" or "smarter" and by extension "better" than everyone else. They use copy/paste "arguments" and Googled "Funny Atheist Pictures" to contribute to religious discussions.
Unfortunately, a good number of my friends fall into the later of these Athiest two groups. In real life, they're under-achieveing individuals of around average intelligence who are wrong about ... well, everything. They harbour an extreme sense of entitlement and think they're owed something for simply being born, and their political opinions could be described as "bat shit fucking crazy" pretty accurately and boil down to "No one else is allowed to think, feel, or believe differently to me, and everyone who does is wrong because I'm smarter than them."
For believers and non-believers, the seconds groups are the most vocal. In forums such as this one, the second group of Athiests are generally the loudest. The "die hard" believers generally don't come to places like the Escapist, 4Chan, World of Warcraft, etc., and so you don't see too many of them.