Dating someone with a weird hobby
The thing about weird hobbies is, every hobby is weird if you think about it enough. How weird is it to get emotionally involved in watching someone else play a sport on television? Pretty weird. Is it really that much less weird than collecting stamps or being a history buff for one specific battle that happened two hundred years ago?
Frankly, I find the only thing that's truly weird is someone who doesn't have a hobby. Most of the time, if you dig far enough, you will find out that their hobby is actually "watching television." BORING.