At my workplace, we have at least one Ping Pong table on each of our floors. Next to each table we used to have a box with 4 rackets and a ball. People came, played, and then left the rackets in the box. Since not everybody was careful with them, the rackets we found were usually in bad shape, which was rather disconcerting. Some smart guy found a solution; the next time he found a racket that was relatively new, he didn't place it back in the box but instead he took it back with him, and it's possible that he (involuntarily) prompted his mates to do likewise.
So now the situation is a classic tragedy of commons. If you find a racket in the box, you can slink away with it or be a saint and put it back in the box. If you nick it, you'll probably get to play whenever you feel like. Keep it back and you'll probably never see it again. So everybody claims any racket they find. They don't do it out of malice, but simply because it is a rational being's dominant strategy. Consequently, people like me who've not (yet) shoplifted a racket never get to play. At least, not on a whim.
What got me thinking is that the people in this "experiment" (I call it that because it makes me less frustrated) are some of the most pampered folks in this country. They earn enough to satisfy their needs, wants and more, and could easily afford a racket or thousand, and our office is arguably one of the best workplaces around. If this is an indication of how highly educated, privileged people instinctively treat their shared resources, then the outlook for humanity must be rather bleak.