I don't think this is specific to just Nissan. I've known Mazda dealers, GM dealers, and a few others to act like this.
I've also known dealers that are wonderful to deal with. When you take away the brand of make from dealerships, you realize that they are individual businesses, run very differently. They are in it to move vehicles, service vehicles, and move parts. How they make their profits from that ranges in a variety of practices, some above board, some very shady.
I agree, dealing with an ahole dealership is not a pleasant experience.