To answer the OP original question, if you're a new member with a referral from a current member, then both of you get entered into a separate drawing for ///M schools (and other prizes). The more referrals current members get, the more entries into the pot:
https://www.bmwcca.org/membershipdrive
One of the biggest perks is the member rebate and its a no-brainer. Get anywhere between $250-1500 rebate on CPO/new vehicle.
https://www.bmwcca.org/vehicle_rebate