I really don't mean this to come off bitchy or offensive (seriously), but this isn't a perfect world.
Some people are going to get offended, and if some of them are purposely trying to look different, then...I dunno. If one is trying to look like a guy or a girl, then they should be prepared to be treated as such.
The second people stop treating people on based on their gender someone else is going to be offended because they aren't being treated based on their gender.
It's impossible to make everyone happy.