By living at home,they will spend That's half the typical cost at a four-year state school, and a fraction of a private university's Adding room and food charges and fees at renowned universities can boost the bill as high as $50,000 a year!

VOA: standard.2009.12.14

And if the other guy does tidy up, hey the room's clean, Who cares? So either way, you're not going to tidy up and you end up with a typical Yale dorm room.

要是别人打扫完了,屋子干净了,我赚了,最后谁都不去打扫寝室,寝室当然就脏了

耶鲁公开课 - 博弈论课程节选