Are you referring to the Marriott Visa anniversary (Cat. 1-5) or Bonus Program reward night certificates (Cat. 1-4)? If so, I've never heard of anyone converting a reward night certificate to points. I don't believe it is possible, else it would have been discussed here on the forum, as there are many who have expressed challenges with marrying up locations of Cat. 1-4 properties with their travel needs (or else prefer the premium Marriott brands) as well as many who have expressed the wish to have the ability to combine certificates for use at higher category properties (which is also not possible within the parameters of the Marriott Rewards program).
You may find the referenced thread below useful, as it offers suggestions and recommendations for some category 1-4 properties that others have enjoyed using their certificates at. Perhaps you will discover some properties out there that you might enjoy using your certificates at. If you do, please tell us about these properties and your experiences.
Really any reward night, regardless of origin. Right now, I don't ever use hotel points for for free nights. The current Megabonus is useless to me, as I'll never use the free nights I accrue before they expire. I travel mostly to work, and with 2 small, I have only traveled with them to locations where we stay with family. I would prefer a choice of free nights or points with the Megabonus, as I would rather go shopping with the points, or convert them to gift cards. That is one advantage of IHG's priority club over Marriott Rewards, where although the points required for comparable gift cards and merchandise is higher, they throw a ton of points at you through tons of promotions.
So in short, I don't care for free nights, I want the points for gift cards...
thanks for the reply!
I see. The Marriott Mall does offer a lot of very nice merchandise. There are sometimes Megabonus offers that award extra points for stays, like an extra 35K points (or more) for 15 nights (or more) or something akin to that. Consider giving Marriott Customer Support a call and asking if they can enroll you, or switch your Megabonus enrollment. It might be worth a phone call.