[sangnoir]

> Are people really that incompetent they can't change one?

I suspect they don't want people stealing/replacing spares in rentals with worn ones[0]. The mere possibility of this adds 1 more thing that has to be inspected and kept track of.

0. I once managed to run down the battery on a U-Haul by keeping the emergency blinkers on(!). I didn't have jumper cables and thought I'd hot-swap it with the one on my car to get it charged: which is how I discovered that batteries in U-Hauls cannot be easily removed. I ended up getting a tow truck to jump-start the U-Haul many hours later.