Pros
Pay higher than minimum wage even as a general customer assistant. Have night shifts available to willing staff. Have a good scheme for promotion of inside staff to leader roles
Cons
Being in control of the smooth operation of the cashier desks is called F.C.-ing, F.C. stands for frontline-controller. They do a lot of work but get paid the same as regular cashiers who have less responsibility and less stress to deal with on average. To progress in the company from a lower position will likely require you to show your ability to handle responsibility, but this could be for an indeterminate amount of time, as far as I have witnessed. If you are a Christmas temp, then there is a very slim chance you will be kept one, even if you prove yourself to be more than capable. Not the staff's fault though, simply a budgetary issue. Having multiple team leaders and a frontline-controller per cashier desks can confuse signals for staff in need of direction. Attitude of different leaders can cause different management styles, some less helpful than others