When you talk about well-endowed schools, it’s good to keep in mind that just like every other form of wealth in this country, the vast majority of the endowment money is concentrated at the very top of the pyramid. The number of schools that can be said to be reasonably indifferent to tuition revenue can be counted on your hands. (Maybe you’d have to take off your shoes if you include some wealthy LACs on a per student basis.)
Even when you look at Harvard, you have to realize that that huge endowment isn’t just supporting the undergraduate population - it’s for the whole school, which is about 3x bigger in terms of students.