Who's Criterion and why do they get to release a special version of a DVD in competition with the normal version of the DVD?

I know they release special versions of supposedly good movies for film enthusiasts, but why are they allowed to release their's the same day as the normal DVD?

Likely because Wes Anderson's a big Criterion fan and it's in his contract that they get to do the special edition.

Criterion has done several cooperative titles with Disney/Miramax; it's not like Criterion gets to keep all of the profits from their version.