Earlier quoted context omitted.
> there's one big difference, though. To shop at Costco you have to buy twice as much (plus typically pay membership fees). That step could be too steep for the people most living hand-to-mouth, even though it would save them money within weeks. So there could be sample bias here too. See the article Why Can’t Walmart Be More Like Costco? [0] for more on this. 0: http://www.thedailybeast.com/articles/2012/11/26/why-c…
I ran into this today when buying TP. I actually just wrote about it. http://stfudamnit.com/2013/05/04/poverty-toilet-paper-and-th...
It means things are directly comparable across brands and sizes ("how does this 117g portion compare to this 270g one?"). It's a fantastic bit of legislation.