Actually, there is an argument against cars. The problem is there is not enough of an incentive to do anything about it as gas prices are still affordable enough not to do anything. Of course affordability is different for everyone, but until they increase gas prices to a point where people really take stock in how much they drive and start drastically cutting back, nothing is going to be done.
Sure, we have hybrid and electric cars, but they don't make up enough of the total number of vehicles on the road to make an impact. Oil companies are still making money, because people are still buying cars and filling up with regular gas. No viable alternative has been developed on a scale that could possibly replace internal combustion engines that run on gas.