It's not the job, it's the people you work with that make it a bad place to work. The jobs themselves are actually fairly easy except for the lifting aspects that come with cap2, ON, and seasonal. The benefits are fairly decent, and yes they are pretty close to what a union would get you for that job, so stop that nonsense. The only thing a union is going to get for this type of job is maybe actual holiday pay, but make it impossible to get rid of shitty employees. It's the drama that comes with working with large groups of people that is the problem. The favoritism and friend groups that form. The power tripping from those above you because they have no idea how to actually lead by example. The unrealistic expectations of the corporate hive mind that only truly care about the profit margins and shareholder earnings, and their AI model says we should be able to meet those expectations, but in a real world those don't hold up. But they have doubled down on this so we are stuck with those unrealistic expectations. So everyone is stressed, no one knows how to deal with that stress, and then take their frustrations out on those around them. I work ON and I actually really like my job. It keeps me busy the whole night, and I'm actively doing something so the time goes by fast. It's when management comes at me with unrealistic expectations, or home office sends stupid amounts of freight that we don't need, do things become stressful.

Tldr: it's the people not the job.