Well, considering I'm in the IT/CS group and I don't use those tools, the idea that "everyone" uses them is demonstrably false.
Secondly, the fact that it's the most probable explanation of the link between facebook/dating sites, and it hasn't been mentioned yet....clearly they're not that popular.
Finally, can people stop thinking that the way they use the internet is the same way everyone does? That's so far from reality it's not funny.