Also according to the agency page there is no refund if you request an exit but are later upgraded.
I would actually question the legality of taking payment for something which you then then have influence over and don't deliver.
The main people this will hurt is platinums. They fly frequently and now have to pay $$ to get the comfort of exit rows. They then have a better chance of being upgraded and lose the $$.
Not a good way to foster customer loyalty.
blechh
lme ff