Pros
Bizarrely, it is the customers that make working there worth while. Most are happy to take advice and have a laugh when trying glasses. Also, with everyone (generally speaking) being so anti store manager, it creates a strong team environment.
Cons
The store managers are put under a great deal of stress to reach targets, some that they have no control over. As a result, managers just end up demanding all sorts from their staff, things like increasing eye exam volumes and litterally harrassing customers as soon as they come into the store. The stress they are put under then feeds onto others and can quickly turn into an unpleasant place of work. Often you would be asked to work until a certain time (for example 6pm) but because a customer is still in the store, you would be forced to stay. Although this is understandable, the conversation of regaining that time, be it in lieu or paid, would more often than not be a waste.