The posts about how making 220 is not all that different from making 220 may be true, but ignore the market.
If 220 was profitable, it would likely be done.
The problem is lack of demand, the way I see it...and the lack of demand comes from ignorance of the product.
You would be surprised just how many medium format film photographers are out there who don't even know 220 exists, or who know it exists, but have never used it, because they simply don't know that it is the same, only better for most purposes. I know people who will shoot roll upon roll of 120, using a film that is available in 220, with the same development to be performed on all the rolls, while their 220 inserts for their back sit in their camera bag never to be used again. Then they will pay $6 per roll to develop the 120 rolls, instead of paying $8 per roll to develop half as many 220 rolls. When I ask why, they have no answer, but continue to go on using 120 only.
120 is the more versatile film, as I cannot think of a camera that shoots 220, but not 120, but I can think of plenty cameras that shoot 120 only.
...but with all the people out there who own relatively modern medium format cameras like Hassies, RB/RZs, Bronicas, Pentaxes, etc., and the fact that these people very often (if not most of the time) shoot more than 10 to 15 shots in a shoot (sometimes shooting dozens to hundreds of pix, in fact), all intended for the same type of development, the lack of use of 220 film amazes me.