They figured out they could create a lot more industries if we all had to drive our own separate vehicles. Road crews, traffic police writing tickets for all kinds of infractions, insurance companies, bank loans, gas stations, oil changing places, constant maintenance, tires, car lots, parking garages, hell, the people that have to scrape up dead bodies off the roads after accidents, etc etc etc. All done to squeeze even more out of the commoner.
Judge Doom: A few weeks ago I had the good providence to stumble upon a plan of the city council. A construction plan of epic proportions. We're calling it a "freeway".
Eddie Valiant: Freeway? What the hell's a freeway?
Judge Doom: Eight lanes of shimmering cement running from here to Pasadena. Smooth, safe, fast. Traffic jams will be a thing of the past.
Eddie Valiant: So that's why you killed Acme and Maroon? For this freeway? I don't get it.
Judge Doom: Of course not. You lack vision, but I see a place where people get on and off the freeway. On and off, off and on all day, all night. Soon, where Toon Town once stood will be a string of gas stations, inexpensive motels, restaurants that serve rapidly prepared food. Tire salons, automobile dealerships and wonderful, wonderful billboards reaching as far as the eye can see. My God, it'll be beautiful.
Eddie Valiant: Nobody's gonna drive this lousy freeway when they can take the Red Car (streetcar) for a nickel.
Judge Doom: Oh, they'll drive. They'll have to. You see, I bought the Red Car so I could dismantle it.