Pros: wonderful customers and co-workers, schedule flexibility, pleasant store atmosphere
Cons: no opportunities for advancement, no performance reviews, low wage with no increases, fluctuating hour availability
This job is won or lost in how passionate you can become about the product you're selling; you need to care if your customers find the right thank you card for their dog walker, or the right picture frame for their mother, or that perfect Valentine's gift. The product and store atmosphere are the parts of this job I can't imagine trading. That and my co-workers. The type of people working in card stores are usually the cheerful, optimistic, friendly kind, which makes your co-workers become your friends, especially in such a small store environment with so few staff.
However, the job is not without its downsides. There is very, very little opportunity for advancement with a staff that small. And in non-peak seasons (from March to September, essentially), head office cuts payroll hours significantly, meaning fewer to go around. And there are no benefits to be found unless you are a full-time employee - meaning a full 40 hours, not the maximum of 35-39 they might give a non-management associate. And it can be hard to make a living when the pay is one step above minimum wage, and you don't receive regular performance reviews to have a chance for a wage increase.
Overall, I would recommend the job if you are looking for a pleasant place to go to work everyday, with no aspirations of growing a career there or saving up any "extra" cash.