The online job application for this was pretty straightforward. (although I accidentally applied for the wrong position the first time. The manager called me and instructed me on how to fix it.) I got called back later and scheduled for a group interview. The interview was very fun and interactive. It started out with meeting a couple of the managers and then watching a slideshow presentation on the company. We then went around (there were 10-12 people) introducing ourselves and stating why we wanted to work at REI. After that we split into smaller groups - one station was a discussion on what customer service means to us, another had us talking about the REI motto and which parts of it were most and least important, and yet another station was where we had to pick random items from a table and "sell" them to another person. I grabbed a flashlight and talked about it. When I was playing the "customer" a guy grabbed a rolled up hammock but actually had no clue what it was, but he just went with it when I said I wanted to buy a hammock. (He got hired as a cashier.) They just want to see how you interact with people.
I wore just nice pants and a sweater. Some people showed up looking very unprofessional (t-shirts, sweatshirts, jeans) and if I remember correctly most of them were not the ones who were hired. I remember one guy who had never been to an REI, didn't know what it was, and just wanted a job for the sake of having a job. He is an example of who was NOT hired. The managers just want to see a passionate person with an interest in the company. They want people who WANT to work at REI, not just someone who needs any old job. Since I was in the group of employees hired for a new store that was opening, 40-50 of us total were hired from the several different group interviews that were done.