Aww, OP, no! You may never know, there might be at least one person who's desperate to find fic for her/his non-existent fandom, so you actually might make someone's day by sharing your writing. Of course, if you're looking for a larger audience, that's a whole other thing, but really, as a person who tends to often get into tiny fandoms (and I actually got sucked into fandoms because of well-written fanfiction before), I'm eternally grateful for those people who share their fanfic on the internet, regardless the size of the potential audience.