Where do you live that car prices are not clearly displayed on the windows? You just walk through the lot, brushing off the salesmen, and note down the prices listed in the window. That's what they want you to pay, and if you're a fool that's what you'll pay. If you're smart, you'll go through a little of the song-and-dance that knocks a significant amount of that price off. Unfortunately for spergy Internet people, that's how buying cars works; I don't much like it either, but if car dealers worked like Amazon, you'd see a Honda listed at $20,000 and that's what you'll pay, like it or not. This way you do get the option to bring it lower, sometimes all the way down to invoice price, because as another poster points out, car dealers don't necessarily make their money that way.
I should have mentioned... I was shopping for used cars. They tend not to place them on the windshields of used cars in actual dealerships in the GTA. Some "show models" perhaps of used cars, but not all.