I'll be the first to say cars I rent don't fare much better.
On a related note, here is a car I bought from my friend last summer for 500 bucks. It saw a much more gruesome fate over 2 months than most cars ever endure. It started as a normal car with minimal body damage and no mechanical problems at over 200k miles. Combine that with the entire field my family owns.
I do not see any humor in this, these guys are total idiots, to treat any car that way is stupid. I have rented many cars, mostly Cadillacs and Lincolns, and I have never abused any of them. One of the best cars I ever had was a 1989 sedan de ville that was an AVIS car. This car has been almost bullet proof, in fact, I still have the car and I bought it in October of 1989. We traveled all over the country in it and never had a problem. I also have a 1994 Concours, a 2009 DTS, and a 1976 Olds 98.
I gotta side with jock82 on this one. This just encourages people to abuse rental cars. Remember the morons abusing the DTS in that youtube video earlier? Sure, they're just rentals, but they will eventually get sold to someone who needs it for transportation. These are adults acting like 12 year olds whose parents didn't bother to teach them any responsibility.
I don't see what the big deal is. Buyer beware. You get what you pay for. I would certainly buy a rental if I was looking for a truck or commuter car as a second vehicle, but I would keep in mind that it was messed around with like a toothless whore.
Reminds me of a bumper sticker I saw in New Mexico: "Where are we going? And why am I in this hand basket?" Lack of respect for something that is not yours is a root cause of many of today's problems..... What would you expect a friend to do with your car if you lent it to him...or to your girlfriend if you let him drive her to the store.....