Wow. Reading through these comments, some people need to grow up.
OP, I guess some girls are hairier than others. It could be as simple as that.
I know it must not be very nice, especially with this huge emphasis upon female hair removal nowadays. If it really bothers you badly, you could think about laser hair removal? Or maybe it is worth a trip to the doctors, just to rule anything hormonal out. I know you say you don't have a problem but you never know.