try it all (in small amounts) and see what your gymgoers buy. It might surprise you... they may spend $$$ on wrist wraps or glutamine or smoothies or short cut white socks or whatever else.
I tell ya, the WORST thing is training, putting on fresh clothes to go out, and realizing you forgot to bring fresh undies or socks with your change of clothes. MANY times I would have paid $5 for a fresh pair of white socks before heading out.
