But between you and the previous renter it may have been driven by an employee or transported across the country by truck, or just damaged in the lot by the person renting the car next to it five minutes earlier.

I found the walkaround off-putting initially (years ago). Especially when you get it wet from washing and this it hides all the minor damage. But they have pretty lax rules about what counts as damage.

The best though, is those airport lots with cameras that record the condition of the car as you drive out.