I think it's because many people simply don't have enough money, so the debit cards would not work when they charge something unexpected.

But with a credit card, the car company gets their money, even if the client doesn't really have enough to pay for it.

Bitcoin would solve this in the same way that a deposit would solve it.

nullama

You gotta iterate over a few rental companies to find the ones that dont make you show a credit card. 

nerd2ninja

nemo

bitcoin

Title basically says it all. I travel a lot and despise credit cards. I cut all of mine up even before I was all-in on Bitcoin. I often have difficulties using my debit cards for rental cars, and sometimes even hotels. 

In a bitcoin economy, can both users and companies be happy?