maybe hes new to cars and was told by someone to do that? who knows? but calling him a moron and making comments like i bet you put your car in N at lights so you can roll back is being a douche.... he could have just said well thast not good for your car blah blah blah instead of making fun of him then saying hes gonna race him and look at him in the mirror

edit: also you know how a salesman is a dealership they probably told him it was made for that