The pay is a big one. You make minimum wage or slightly above, and while you can get a raise yearly (during your review) I never knew anyone who got more than 26 cents. Often you'll get less. That isn't terrible if it happen more often, but since you start at such a low rate, a twenty cent raise once a year isn't much to live on.
The hours. Shifts are super inconsistent. During holidays they will overwork you, and the second season is over they start cutting shifts like crazy. I would go weeks with getting no more than call-in shifts.
Call-in shifts! You have to call-in two hours before you are scheduled to see if they need you. They also have on-calls, an example shift would look like this: 2:00-6:00 on-call till 8. So you could be off at 6, or they could keep you until 8. Even without the oncalls, I was never going home on time. I was often there at least half an hour past my off time, because there would be go backs that you weren't allowed to do until you were off.
The managers were catty. Every year employees take an anonymous survey about what they think about the workplace. When my store had the results come in, the managers were not happy to see that we employees had not scored our store very well. They spent most of a meeting trying to get people to admit to who said what. They were even writing down what people said! The survey is anonymous for a reason. Our managers said that we didn't understand the questions, and that is why they got a negative score. Instead of using the survey how it was intended, they acting like we were dumb.
Very, very little training. Especially cashiers. We were thrown at the front to fend for ourselves. Often they would hire new cashiers during holiday, but they would not train them. When the new cashiers were slow, they were yelled at and belittled over the headsets for every employee to hear. We had cashwrap leads, but they never did anything. They rarely even rang.
Inconsistent managers. One wants you to do something this way, another yells at you for doing it that way. They aren't clear about what they want. When the GM closed she would make sure the people she liked closed with her and they would just hang out. Opening the next morning was more like closing, because the store would be an absolute mess. If another manager were to do that though, they would get shouted at.
No opportunity to move up. In the three years I worked there, the only change to happen in management was a GM left. This allowed two managers to move slightly, but that was it. Those in upper management rarely ever move up, which means YOU do not move up. There just aren't any positions. During holiday there are some opportunities to become an elevated employee, but those positions are temporary. You will not get to keep it.
Lastly, the turn around! I constantly had no idea who I was working with, because people came and went like crazy. In one day we had six people just stop showing up. The next day we had three. A lot of new hires are 18.