Take it back to the dealer...
Mine doesn't do that. Sounds like some kind of computer sensing problem. This would certainly waste a little gas and probably put extra wear on the engine as well. Also, you would either have to sit after starting until the idle comes down or certainly put extra wear on your transmission when shifting into drive at high idle.
Take it back to the dealer. Unless it's a faulty computer chip, you're going to have to leave it at the dealer at least until the engine cools off completely so that the dealer can see the problem.