1. Training is often rushed.
2. While the attendance policy isn't terrible, it is frustrating to know that you will accumulate points for things beyond your control. End up hospitalized? You'll get attendance points. Have a baby? Sorry, that's not a protected status. You'll get points.
3. Retention is virtually non-existent. A big part of this is because raises, too, don't exist. You'll get hired and likely be making the same pay 3-4 years later unless you get promoted.
4. Once you do get promoted, plan on working at minimum 45 hours a week, and probably more like 50. During particularly busy seasons, it could be as much as 60. Remember, promotion means salary pay, so you don't get compensated at all for these additional hours.