In "Marriott Rewards" you can click on How to Use Points then Hotels then Points and Categories then enlarge the pop up and in the upper right corner you'll find a Category drop down.
The address below may get you there quicker than following my instructions above
Try going to Marriott Rewards Points | Redeem Marriott Rewards Points and click on "Convert Points into Categories." You'll get a pop-up window with the points for each reward category and in the upper right corner of the window it a drop-down box where you can view all the hotels in a particular category. You'd have to look at each point category to get a full list, but it will at least give you everything in that category.
I find this helpful when looking for a hotel to use up promo certificates (start at cat 4 or 5, depending on the cert and work down). Not sure if this is exactly what you want, but it might be close.