One of my concerns about an automated taxi system is that they'll become dirty and decrepit even faster than public transport because there's an increased level

One of my concerns about an automated taxi system is that they'll become dirty and decrepit even faster than public transport because there's an increased level of privacy and nobody to maintain the vehicle between riders. How would you enjoy running late for something and the taxi pulls up, its seats covered in vomit? Eventually, all cars may be scratched up and 'tagged'. Maybe this won't be as widespread a problem as I think it could be. Zipcar seems to be rather successful, although I've never used one.