@djc But, for example, the US practice of using sliding-scale pricing to finance private higher education is a horror. The percentage of families who will send their kids to sticker-price-expensive colleges is small, and making the sticker price very high to subsidize cheap rides for the poorer concentrates a terrible burden. The problem, of course, isn’t the cheap rides. It’s that we should all be subsidizing, not just a small, adjacent class of parents. /fin