Vantaggi
REI is a company that honestly believes in its mission to get more people outdoors with the right equipment to enjoy it while at the same time encouraging good stewardship to preserve outdoor spaces for generations to come. Most customers are happy to be in the store so more often than not customer interaction is very positive. Management has been genuine, supportive, and easy to talk to/work with when questions/concerns arise. I have worked across several stores and have experienced this in every one. Also, their profit sharing plan (they are a co-op) is quite nice and they also offer pretty good benefits to employees (especially for a common retail position). Each store has a break room and an employee shower in case biking/running to work is your thing but you don't want to work in sweat drenched clothes all day.
Svantaggi
Just like all other retail, the hours available are always subject to the ebb and flow of customers and how much they are spending. If you are in a constantly high traffic store (or one in a particularly wealthy area) it is a lot easier to get the hours you will need though.