I would argue that financing a purchase (say, a house or car) falls into this category. The object itself does not change price, but the financing will change price wildly depending on whether the parents have good credit and can cosign the loan.

This one makes sense to me cause the price (interest) is related to the risk or repayment. The way the universities do it is they want to find out how much money is in your parents bank account and then take as much of it as possible.

True, although that's sort of the opposite. If your parents have resources and choose to help you out, the car loan will be cheaper. If it were similar to the college scenario, the dealership would say "your parents are rich, so we're going to charge you more because they'll be able to afford it". Of course that would never work because there's competition in the auto market, while prestigious colleges are effectively a cartel.