BMW must have really wanted a small fortune for licensing. (greedy *&%^*$!) I noticed that the Mach Go (Speed Racer Mach 5), Mario Bros., and Ultraman cars also command top dollar - probably because of the licensing agreement....
Could be that they cost the same as "regular" BCG in Japan, and exporters are just charging extra for the "special" models.
Maybe a clone manufacturer will make a (non-licensed) mini-cooper body and call it a "BWM mini clopper", like the "Hodna S2001" clone I have...