This is simply a business decision. RMP has looked at their numbers, made a few projections and figured they can deal with the loss of certain brokered items. The sheer volume this site does pretty much gives them carte blanche on what they want in their sandbox. Art and Business do not get along very well, but they can be made to play together in a stiltedly amicable way. As a broker, you need to look at your bottom line, make a few projections and see if you can deal with the loss of sales. Or if you need to seek a different brokerage for what RMP no longer allows to be sold in their sandbox.