I'm not sure why you think, if they were fully funded by the public, that they would not also continue to go for private capital in addition to those funds. Anything extra they can juice out of alumni, corporations, and "donors" would be gravy for their endowments, and allow them to gold-plate their administrative salaries. The steeper the line goes up and to the right, the better for them. No organization, private or public, profit or non-profit, turns down money they could potentially get.