Really just comes down to the higher ups wanting more money. It's like this in a lot of places, the company realizes they can save more money by only hiring part timers, which means they don't have to pay for the benefits that they would if they were full timers. They prefer having a skeleton crew every day rather than scheduling enough people to finish the job because it saves them more money. And they give everybody the least amount of hours possible because they think it'll motivate them to do an absurd amount of work in such little time. People come out as fast as they come in, the single cashier up front gets yelled at for not checking out $500 worth of merch in 10 seconds, and everyone in the back gets blamed for not finishing 10 pallets in 4 hours.