Gas prices aren't as high as they were last month, but still high enough that I've seen several reports of attempted gas siphoning from their vehicles.  If you go to your car in the morning, and you see you're gas cap removed and your door open, there's a good chance that's what happened.  Fortunately, these low life piece of crap criminals usually can't get anything from modern cars, and there are several reasons why.1.  Most cars have a screen in the filler neck that prevents a hose from going thru.

2.  Most modern cars have a check valve of some type that would require tools to break or remove.

3.  Some modern cars have a flapper inside the fill hole that makes removing a hose very difficult.

Here's a video that explains it in more detail: