Why NECA would not release these headsculpts as 1:6 is beyond me. They are fantastic. By the time they get to 1:12 and the manufacturing process much of the detailing will probably be lost.
Because they only get certain scales in their license, where their main product size is 7", they probably don't always pay for the 12" license, if they can even get it. They might go after Rocky, but it seems like with NECA, the 18" and 7" scales sell best, 12" not so much.