Your flight arrives late. You claim your bags and walk to the rental car counter in the airport. No one is there. You are in a hurry to get to your destination. You consider your options. Bus? No, your destination is too far from the city. Taxi? No, too expensive for the distance you have to go. You walk out into the parking lot and find a car with the doors unlocked. You get in and start it with a screwdriver. Then, you drive to your destination.
When you come back to the airport, you drop the car off at a police station. A cop looks for damage to the car. You pay a fee about what a normal rental car would cost, which goes to the owner of the car. Then, you pay for any damages done to the car in the process of stealing it and using it. Finally, you take a bus or taxi the rest of the way to the airport.
Car owners would have the option of paying a fee to opt out of legalised car theft. Those who opt out would get a special license plate or a window sticker indicating that the car has been opted-out and is illegal to steal.-- crj900, Aug 12 2013 P2P Car Share https://relayrides.com/ [MechE, Aug 12 2013] It would still be legal to lock a car or use a car with an anti-theft device. Stealing a locked car or one with an anti-theft device would be legal, but the person who stole it would have the extra effort of breaking the lock or anti-theft device and would have to pay for the damage when he/she returned the car.-- crj900, Aug 12 2013 Interesting, but I'd prefer an opt-in system...-- scad mientist, Aug 12 2013 So basically my link, except with the added inconvenience of your car not being there when you get back?-- MechE, Aug 12 2013 Of all the ideas you've posted so far, [crj], your third one is far and away the best.-- MaxwellBuchanan, Aug 12 2013 I'm presuming that the window sticker / license plate is somehow difficult to pull off of the vehicle.-- RayfordSteele, Aug 13 2013 why not just legalise airplane theft, then you could go straight home. you'd need a big garden obviously-- notripe, Aug 13 2013 random, halfbakery