For those interested in learning more about Costco, this is the most informative, fascinating, and mind-blowing report I have ever read:

Understanding Costco by Coriolis Research (namely, Tim Morris). http://www.coriolisresearch.com/pdfs/coriolis_understanding_...

Some mind blowing facts:

1. They pay their employees $10-$17/hr as opposed to Walmart (as discussed in the article)

2. CEO earned 350k in 2012, only twice that of a store manager at Costco

3. Margins are razor thin. In fact, an employee got yelled at for selling something at a higher margin (even though all the products were successfully sold within a week)

4. ~40% of Californians have a membership

5. 30% of inventory is at the store within 8 hours

*Note: My employer is a consultant for Costco, and I might be too, so I'm definitely bias, but I love the company.