Trust me coworkers want nothing to do with you. You are going to be working in a large place. With many coworkers. Almost no one knows you or cares about you. Just work as little hours as you can to buy the shit you need
How much customer interaction is required of an overnight stocker at Wal-Mart?
In my honest opinion, this will be a good job for you if
A) You don't have to interact with customers (or if you do, not much at all)
B) Your supervisor/manager isn't an asshole
C) Your co-workers are pleasant enough
Just work enough hours to be able to afford to help your folks with the bills and take care of your own bills and buy some nice things for yourself. Thing is, there's probably a good chance that your manager is going to pressure you to work more hours than you want to at some point. As a part-time staffer, you're going to be expected to cover for full-timers now and then.
Having a whole bunch of free-time isn't very fun if you don't have any money to enjoy it.
I might sound like a hypocrite because I have been unemployed now for 3 months (I can't believe it has been that long!) But I have saved up a lot of dough after workcelling for over 4 years. And the Canadian government is paying me $916 (after-taxes) biweekly until January 2016 for partial wage replacement after losing my job (employment insurance). I have no immediate urgency to work anytime soon.