Much like the used car sales industry, the rental car biz can be a little shady. Like so many industries that take advantage of their customers being stranded, rental car companies are known to try and rip off their customers for every cent–however, one diligently vengeful traveling employee saw to it that his continued business was far more valuable than a tack-on fee.

Getting things for free doesn't mean that you're not paying for it in some way. That is especially true when it comes to rental cars. They always claim that you're getting “free miles” or “comped gas" or an “upgrade at no cost”, but somewhere in your contract, and somewhere on your bill, you're probably paying for it anyways.