Perhaps, but the small portion of 721 conveniently chosen for the quote pertains to owners who are delinquent in paying their annual fees and is in regards to the "managing entity's" right to rent the time (points) of the delinquent purchaser. Suggesting that it refers to someone involved in violating the "commercial purpose" issue is a bit of a stretch as that is not mentioned at all in the 721 document. Used in the context of the document, the quote covers an entirely different and specific topic outlining the responsibilities of the "managing enitity" and it's "fiduciary responsibility" to the "purchasers"- stating it has the option of renting out the time of any "delinquent purchaser" after due notice. If you are including "commercial purpose" renters in the "delinquent purchaser" category then I would agree that DVC has the responsibility to treat all "delinquent purchasers" the same, but I'm not convinced that "commercial purpose" renters would be included in the same category as "delinquent purchasers".
That same section goes on to state in Section (6) (a): " The managing entity of any timeshare plan located in this state, ..., may deny the use of of the accommodations and facilties of the timeshare plan, including the denial of the right to make a reservation or the cancellation of a confirmed reservation for timeshare periods in a floating reservation timeshare plan, to any purchaser who is delinquent in the payment of any assessments made by the managing entity against such purchaser for common expenses or for ad valorem real estate taxes pursuant to this chapter ..."
Section (6) (b) states:"(b) A managing entity desiring to deny the use of the accommodations and facilities of the timeshare plan to a delinquent purchaser and to those claiming under the purchaser, including his or her guests, lessees, and third parties receiving use rights in the timeshare period in question through a nonaffiliated exchange program, shall, no less than 30 days after the date the assessment is due in accordance with the timeshare instrument, notify the purchaser in writing of the total amount of any delinquency which then exists, including any accrued interest and late charges permitted to be imposed under the terms of the timeshare plan or by law and including a per diem amount, if any, to account for further accrual of interest and late charges between the stated effective date of the notice and the first date of use. The notice shall also clearly state that the purchaser will not be permitted to use his or her timeshare period, that the purchaser will not be permitted to make a reservation in the timeshare plan's reservation system, or that any confirmed reservation may be canceled, as applicable, until the total amount of such delinquency is satisfied in full or until the purchaser produces satisfactory evidence that the delinquency does not exist."
The statute later includes the quote chosen by Dean. None of these quotes specifically deal with the enforcement of a "pattern of rental activity" and none of them require DVC to do anything except take required fiduciary steps to collect delinquent fees. Those steps include cancelling reservations providing all delinquent purchasers get the same treatment (Dean's quote).
721's comments about the "managing entity" is pertinent to renting the time of "delinquent purchasers" to recover the delinquent fees and does not appear to limit other rental activity by management.
Interesting read, but nothing here that specifically addresses any lack of ability to enforce the "commercial purpose" clause.