I was just teasing. There has been a more than a few heated discussions on the dark side on here.
I have never tried it myself. It would never work or be safe (in my opinion) on a Sport bike. If I had a heavy cruiser with limited cornering clearance, I would probably be very tempted to try it myself. Especially if I spent most of my time up right and handling was a lesser concern. There are videos on U-tube showing bikes with car tires on them. They are all Gold Wings and cruisers. Most of them mounted cameras on the bottom of the bike to show how the tires react to cornering. From what I have read is they run really low tire pressures to help the tire react to the cornering forces and flatten as it corners.
I have never ridden a bike with a car tire on it, but I have to believe that it would have a more than noticeable effect on the handling. It would slow it down a lot, require more effort to turn the bike, and the bike would be reluctant to hold it's line. I notice it when I get a flat spot on my motorcycle tire. I am sure it would be a lot worse with a car tire. The thing is that you would get used to and not notice the difference after a while. You would probably notice it more if you went back to a motorcycle tire.
I feel your pain. I am already trying to plan my next rear tire replacement. The tires are expensive and they do not last very long. Especially on a sport bike. With the economy the way it is and that I am going back to school, my income it pretty low right now. If I had a cruiser, I might give it a shot myself even thought I have my doubts about it. I would like to ride a bike with a car tire on it once to just see how it does effect it.