To be honest while I hate Parking & Resort Fees, the parking rates at SD really are not all that insane. Yes, Disney was wise and ditched their parking fees. But resorts like the Waldorf $40, Wyndham Grand $40, JW Marriott $38, Gaylord $40 all similar pricing and their locations aren't as good as SD. The crazy one is the TownPlace Suites charging $15.
When staying at SD you need to take the Parking & Resort fees into account with the pricing only then will you have a fair comparison.
We've never opted to use a rental when we stayed a SD, we can use the water transport, walk or busses. For late nights at Trade Sam's we just Uber back. Have fun & enjoy your time at SD!