Am I being paranoid/silly?

Yes.

Paranoid because people answering a few questions in the chatterbox will not turn this site into apache/sql/whatever monks. If anything it will show people that this is a friendly, helpful site and will make them more likely to contribute to it.

Silly because what is said in the chatterbox is very different than what is posted on the site. I routinely hear people talking about movies, music, food, you name it in the chatterbox, nobody complains about this. The chatterbox is very informal and I think it prevents many off-topic posts.