Even if it does seem ridiculous to park your own car, I just told myself it was for the "upkeep" of the lot! And....the hotel was so wonderful it was worth every single penny!!
Yes, b/c the parking fee is to discourage you from bringing a car, then you will spend more on-site. It's the same reason the WDW or USF ticket is not much more for 7 days than 3 days...keep you at their park--keep your $$ at their parks.