I think the issue is I and my peers never really received any education about how to make it in the world (outside of simply "go to college"). If you are working a minimum wage or low paying job you really have two jobs the second being constantly searching for and applying to better opportunities.
Also I suspect another issue is the cliffs for government benefits. If you work between 45 - 60 hours a week for $12 - $13 an hour like I did a few years ago you aren't exactly well off yet programs like Obamacare will fine you for not buying health insurance that you can't really afford. Similarly free clinics will turn you away and I wasn't able to find a single aid program that you would qualify for except about $20 a month in food stamps. I figured out the costs once and there are a great many situations where a rational actor would simply work less or for less money and do better economically.
Yep, wages don't amount to everything. I don't know how Walmart is nowadays, but a few years ago I had a few friends working at one being stiffed an hour or two underneath the weekly "full time" amount so they didn't need to keep up with certain benefits. And making them work unpaid overtime and bullying them into not reporting it or clocking in.
People bring up legal recourse for these situations, but realistically, it's very scary when you're in that scenario and have to actually deal with getting underpaid or not getting paid for a while but having your dignity.
About the tipped wages mentioned a couple comments up, from my experience working delivery, that's a great way to get yourself fired. Because I guarantee you all the employees won't go in together on saying it, you're basically telling the management "I don't get tipped as much as everyone else" which is great grounds for poor performance, it's a catch-22.