Annoying "Tribute" Artists and Songs on the Zune (xBox) Music Marketplace.

Has anyone else noticed that every time they look up a song, there are always a huge number of tribute and "knock off" versions of it in the Zune Marketplace? I find this extremely annoying and am wondering if there is any way to turn it off, or if this is just a Canadian Marketplace issue?

Thoughts or observations? I am especially curious to see if this is the same in the US as well as the other non-US Marketplaces.