You don't ever have to join, most, if not all tournaments sell memberships that last through that event only. I'm not a member yet myself for somewhat the same reasons however I've gotten over the fact that I'm a weak player, and would still like to play some OTB rated games for the experience and fun of it.
I'd suggest you find a tournament that appears to be to your liking and try it out, you can always choose what kind of membership you want at the event, and this way you can scout out one that should have games that aren't too challenging for you.
Hello everyone and I have a question that has been on my mind, I was wondering when someone should join USCF. I would like to join but feel I am to weak of a player. I have progressed alot and I feel I will be able to soon. This may be hard to answer, but what rating would you I think I could at least competitve in USCF. Right now I stay about 1050. I am only 14 years old as well. Please comment.