Dealer auctions are a sort of last resort to move a car that won't sell on the dealers' lot for whatever reason.
Also keep in mind that as new car prices go up, used car prices get adjusted accordingly, so used cars that are in demand, like a 02 LS, don't lose value as fast on the actual used car market.
Also, if you look at 02 models like on AutoTrader you'll see that mileage is the biggest factor in asking price, all other things equal.