Using all the toilet paper in each public restroom. It's a habit.
I have such a reputation that, if you live near me and use the ladies' restroom somewhere and all the toilet paper is gone when you take over the stall, local logic goes I was the one who last used it.
Public restrooms are not always fast when it comes to refilling toilet paper, even when there are multiple spare rolls around to refill it with. Anyone can end up being the last one to use the toilet paper in a restroom and have it be a long awaited issue to fix. For me, it's due to routine bad luck with using the bathroom. Often I end up inadvertently being janitorial with it.