If someone tried to siphon gas from my Civic Hybrid, I'd know immediately because the exterior cover would have to be pried open. It has no key access, only a lever to release it in the car.

As far as airport parking lots go, everyone should know by now that they're basically shopping centers for thieves. They know that the owners are out of town, so they won't get caught stealing a car (or its contents), and the crime won't even get reported until long after the car is stripped and gone.

And forget security. Who are you trusting to watch your car? Some guy making $7 an hour in the exit booth, and another guy making $10 an hour as a security guard. The thief just gives them a couple hundred bucks, and enjoys unfettered access to the lot.

Anyway, back in the real world, even someone as stupid as a gas siphoner would know not to hit a little car with a 12 gallon tank and a protected gas cap. He'd find a full-size pickup with a 25 or 35 gallon tank, and a non-latching exterior cover.

It's a quick hit, and the truck driver is unlikely to notice the 5 gallons missing from his tank.
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