BTW, I generally dislike such discussions of "who is subsidizing whom" because they often miss the obvious point: both "sides" benefit from having a larger mark

BTW, I generally dislike such discussions of "who is subsidizing whom" because they often miss the obvious point: both "sides" benefit from having a larger market to spread fixed costs over. There is no "subsidy" here. Just regular economies of scale that benefit (at least for first order effects) all the users.