Market conditions explain the higher price, but why does the extra money go to the dealership rather than the manufacturer? I think something other than the market is at work here.
It's because they're collecting rents from having state legislation pretty much guarantee they're the only way to buy a car brand (other than Tesla). And though collusion might be hard to prove, it's pretty obvious to a shopper that the price transparency from the Internet is just as potent a weapon for dealers as it is for shoppers.
People are also buying up all the inventory of available cars and flipping them at CarMax for a profit. Look on CarMax and you see loads of brand new cars with 3-6K markup. That's who the dealerships are competing with.
Because my understanding is they own the cars, once they're delivered from the manufacturer. They own the asset.