If some people dont care enough to buy a certain ball (or any balls for that matter) to put in their bag because of its performance (and there are some cheap balls with pretty good performance), why should they care enough to play in a club championship, or any other tournament. You have registration fees and other expenses....I just dont get the big deal here. Its a rule, play by it!

If you dont want to play by the rule of one ball, whats to stop you from playing a Pinnacle or whatever gets you the best distance off the tee..and then switch to a ProV1 for your approach shot on the same hole? Its the same thing. Pinnacle on a par five.....ProV1 on a par 3.

But back to the original post....as far as I know, all stroke play tournaments have this rule, or at least the ones I have played in. So it could be just a rule by the USGA or RCGA. If you play a tournament its governed by these rules.