The things "grandfathered" for resales prior to March, 2011 were not part of the core of DVC, the POS or principles of the club as stated in the contract. They were all components that could be, and have been changed numerous times over the past 21+ years.
There have been many things some have considered to be part of the DVC program that have changed including, but not limited to, transfer rules (one-per-Use Year, then multiple per-Use Year, then back to one-per-Use Yea)r, World Passport Collection partner (RCI, then II, then RCI), DVC discounts and perks (BWV valet service, dining discounts, 10% discount on non-AP park passes), etc. .
Adding the expense for closing costs was certainly a blow to existing members when it went into effect. The cost was previously absorbed as part of the direct purchase and when added, IMO, lowered the direct sales more to what was an expected resale expense. With resales, many negotiate for the seller to cover those costs - with DVC is non-negotiable and all added to the costs for the uninformed new buyer who still has the pixie dust in his eyes.