Re. Criterion's pricing: the reason that Fox can produce The Grapes of Wrath for $15 is that they don't have to pay licensing fees for the film itself, nor negotiate for the best elements to make the transfer from. They own the film and everything to do with it outright.

Similarly, the reason Criterion charge so much more than Blue Underground is that BU deals in mostly obscure euro-cult flicks which cost very very little to pick up. One of the great cornerstone masterpieces of world cinema like Tokyo Story or Nights of Cabiria costs many times more to licence than the likes of Baba Yaga or Salon Kitty.