About locked cars at the dealer.
Galpin Motors, the largest dealership for many different brands (a MEGASTORE) leaves the cars and trucks on the front line locked since they could all be driven off the curb into the street. But the showroom cars are all unlocked, as are all the cars in their locked storage lots behind the dealership. And the keys are in the ignition too. I have gone back there to demo the sound systems on a lot of different cars. And if it's a hot day i will fire them up and run the AC too. They don't care. Maybe that's the reason i have bought several cars from them. And may soon be getting another.
The dealership I bought my wife's car from leaves ALL their cars unlocked outside 24/7 (new and used) and it's nice to be able to check out what intrest you without feeling like you have to talk with a salesperson.