An example of why REI customers retrurn:

We purchased a tent in 2004 from REI to replace our heavier touring tent. It was a great tent with carbon fiber poles and we used it for climbing, backpacking and touring. It was used a lot! One of the carbon fiber poles split on a bike trip last summer. I brought it in to our local REI hoping to buy a replacement pole. They looked up the tent for me, and found out that the carbon fiber poles had been replaced with lightweight aluminum poles to solve the splitting problem. Rather than sell me new poles, or just replace the poles; they opted to give us a completely new tent. It didn't end there-- I purchased the tent in 2004 for full price. The day I went in to the store the tents were on sale, so they gave me a $70 refund. I left the store with a new tent and $70! That is pretty hard to beat.

Of course, they just got some pretty good advertizing from me.