The inflight and ground catering is a small fraction of the ticket price. The additional jet fuel required to fly you and your heavy biz class seat that consumes the space of 3 Y seats is the big expense.

Don't you think if there were a huge market for biz class seats that the majors would already have larger biz class cabins? And they do discount the seats frequently- they just don't do it explicitly in the price, rather by allowing kiosk or mileage upgrades from lower classes.