Hyrule is a cool name and lots of ppl like LoZ, it doesn't surprise me to see the name a lot. There are a few other common ones that are really slipping my mind right now. I like names that aren't based on existing places I guess (real or fictional).
I guess a lot of people use it, but a lot of people like Legend of Zelda. And if having a town called Hyrule makes them happy, then good for them. I don't really care what other people call their town because it doesn't affect me.
I've never bothered to think about people's town names, only ones I dislike are made out of loads of random symbols or something pf. So there's a lot of Hyrules.. it's bound to happen.. go go LoZ representing!