[0]http://news.walmart.com/news-archive/2016/01/20/more-than-on...
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.
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.
IMO that's the strongest argument for replacing welfare programs by a negative income tax, or universal basic income.
Nor do driverless cars have to make up for "idle time". The only legitimate counter argument as to why a taxi should earn as much as they do is that they sit around not making any money for 10-60 minutes at a time. However, that goes away with driverless cars, and any excuse to charge exorbitant prices the way taxis do completely vanishes.