Where was this? Sounds like the kind of things that are extremely variable depending on where you live. When I was working near minimum wage in California, companies would screw me like this. But when I moved to Utah, companies would give me nearly any hours I asked for since they really needed the work done.
Furthermore you have a ton of full time employees who will sing praises about the company. However part timers get shafted hard. Oh you can't work 3 days a week due to school, okay enjoy barely 8 hours a week. There were a lot of people there who had to work multiple jobs simply because they could not get enough hours.
Unless you are fully willing to commit to them it isn't a great place to work.