I agree.

 

If I try to put something in my cart that I have already purchaced,  Rendo's system recognizes that I already own it and stops me from buying it a second time.  How hard would it be to apply that to the rotating sponsored items feature?  After all,  the vendors are waisting their sponsor money showing me things that I already own,  and it would make sense to only have things the logged on user doesn't already own show up there.