Mr. Money Mustache does a case study on shopping at Costco vs. Safeway and analyzes if Costco is worth it.
Episode 162: Is a Costco Membership Worth the Cost by Mr. Money Mustache.
Mr. Money Mustache is a thirty-something retiree who now writes about how we can all live a frugal, yet awesome, life of leisure.
He and his wife studied engineering and computer science in Canada, then worked in standard tech-industry cubicle jobs in various locations throughout the late '90s and early 2000s.
Then they retired from real work way back in 2005 in order to start a family. This was achieved not through luck or amazing skill, but simply by living a lifestyle about 50% less expensive than most of their peers and investing the surplus in very boring conservative Vanguard index funds and a rental house or two.
The original post is located here: http://www.mrmoneymustache.com/2011/09/30/is-a-costco-membership-worth-the-cost