Hey, you're not being silly. That's a valid issue, and it's good that you're concerned about it. Still, if you're concerned about it, you're probably not the kind of person who's gonna be a problem. A fanfic isn't a limited commodity; you can't use it up on the wrong people. You can't hurt anybody just by reading. As long as you're not trying to influence people's tastes, and as long as you can stay respectful of them during discussion, you're fine.