its called freeskiing for a reason, you do what you want. staircases are just another thing to do with the concept of urban skiing, if you dont like it you dont have to do it, that doesnt mean you can or should tell other people its for skateboarders. Maybe somebody out there thinks the stuff you do on skis is gay and should only be done by snowboarders, how would you like that?
Besides I'm guessing you dont skateboard and have probably never hit a staircase in your life.