Getting this back on track to the original question...
Was your respondent challenged as to what the "privacy concern" might be? Because I think they're talking out of their arse. The system is entirely opt-in. You (as the club) don't give RSP your members' details. Your members have to voluntarily go to the Rare Spares website and create an account, linking it to a particular club. They'll get sent a little dog-tag member card in the post.
Each club can check to make sure people listed on their account are actually club members. Rares also occasionally send the nominated club contact a similar list. So the privacy concern doesn't hold water.
When you buy anything at RSP, you show the little membership dog-tag, and you get the club discount price. Additionally, RSP tally the sale against the club, and keep records of how many "points" the club accumulates. The club can redeem these from time to time for merch that will have both RSP and your club's logo on it.
As Graham mentioned earlier, the NSW Club has been part of this scheme for quite a few years. Norm at AAP/RS (our local RSP outlet) has told us numerous times that the NSW FE-FC club is their best customer on this program. We've received an esky, fold-up chairs, a cabana and various other things during the time. Not to mention a few BBQ Breakfasts put on at their branch for us
It's a win-win arrangement, and there's really no downside for anyone involved. Go for it.