Some, but not much. DVC members have to use their points - so they aren't going to trade a point reservation for free dining unless they have another use for their points. Some people might try and rent their points to get free dining, some might add another trip - but I think those would be the exceptions. Most people don't have time/money to add a trip (if money is a motivator for free dining, its probably a motivator to not add transportation costs, pet sitting, et.al for another trip - even if you have annual passes - unless you really live close enough and have an arrangement where visiting DVC is "almost free.").
People who rented DVC points might be kicking themselves, but unless they got a cancellation clause in the contract, they are stuck. And as to the members who might want to rent their points out in order to take advantage of free dining, free dining creates a demand issue.