> still seems weird to me. is there any other product for 18-22 year olds where the price changes depending on their parents wealth?

If by “price” you mean, “net price after available subsidies”, then, yeah: healthcare, housing, and food, among others.

The difference is that the subsidies are usually public, whereas the education subsidies are by the seller—but the seller is also a 501(c)(3) nonprofit, the entire premise of which, and the reason donations to them are tax deductible to the donor on top of the nonprofit being tax exempt, is that the nonprofit functions serves social needs in lieu of the government doing so.