Pros
(Depending on your manager) you can take the tasks at your own pace and do what feels best, based on what you see. The position I'm in allows headphone use if you're not visible to customers.
Cons
Skeletal shifts are the norm, employee burnout is rampant and unaddressed.
Manager turnover is very high at my store, which makes establishing consistency impossible.
I get the impression that the conditions for employees vary greatly by store. That said, if you find yourself stuck at a rougher one, your options are to either take the toll to your physical and mental health, or to quit/transfer to a better store.
I have personally experienced many legal violations at my place of employment.
(keeping the store open and functioning when the workers don't have a bathroom [OSHA fixed that])
(and a few incidents where hours were not properly entered for employees, causing them to work without pay)
I have worked here for 4 years without benefits, one year only missing the hour-cutoff for it by an average of 20 minutes.
Consistent schedules are very uncommon for employees.