In reply to Tyler:
I think the whole idea is its training for winter climbing and you would normally have crampons on however in an indoor wall that's impractical and so you loose the crampons but keep the boots !!
The purist also soaks one boot in cold water before the event to emulate the plunge into the burn on the way in, and should also leave their sandwiches in the freezer for while shaking the lunch box just before opening to ensure all the filling is not between the bread !
Aye Dan