A FlyerTalk Posting Legend
Join Date: Feb 2001
Location: Berkeley, CA USA
Programs: Piggly Wiggly "Shop the Pig!" Preferred Shopper
Posts: 57,074
I'd go up to $25 for a decent airside gym, but I suspect that I'm less price sensitive about this than most travelers. My wild guess is that you start losing lots of customers north of $20.
Does anyone know if any big companies have policies about gym fees while traveling on business? That might be a useful piece of info. for the OP. If there are such policies, how much is reimbursable?