Higher minimum wage means the poorest people have more money, then they turn around and spend that money at Walmart.
The poorest people do not directly benefit from minimum wage, because they don't have jobs. Many participants in the informal economy are also very poor.
One option I didn't think of in the ancestor is that people pushed into the informal sector may still be showing up as employed in the sources being referenced: people making a lower-than-minimum-wage living as e.g. junk collectors are sometimes counted as such depending on methodology. We could pick out this effect by asking for personal earnings as well as employment status: if higher minimum wages are coming out of corporate margins somewhere, we'd expect average earnings (at least in the lower segment of the workforce) to go up, but we wouldn't expect that if it's pushing people into the informal sector. A survey would probably have to be carefully designed to have the resolution to pick this up, though.
Note: Originally posted in Discussion, edited to take comments there into account.
Yes, politics, boo hiss. In my defense, the topic of this post cuts across usual tribal affiliations (I write it as a liberal criticizing other liberals), and has a couple strong tie-ins with main LessWrong topics:
The issue is this: recently, I've seen a meme going around to the effect that companies like Walmart that have a large number of employees on government benefits are the "real welfare queens" or somesuch, and with the implied message that all companies have a moral obligation to pay their employees enough that they don't need government benefits. (I say mention Walmart because it's the most frequently mentioned villain in this meme, but others, like McDonalds, get mentioned.)
My initial awareness of this meme came from it being all over my Facebook feed, but when I went to Google to track down examples, I found it coming out of the mouths of some fairly prominent congresscritters. For example Alan Grayson:
Or Bernie Sanders:
Now here's why this is weird: consider Grayson's claim that each Walmart employee costs the taxpayers on average $1,000. In what sense is that true? If Walmart fired those employees, it wouldn't save the taxpayers money: if anything, it would increase the strain on public services. Conversely, it's unlikely that cutting benefits would force Walmart to pay higher wages: if anything, it would make people more desperate and willing to work for low wages. (Cf. this this excellent critique of the anti-Walmart meme).
Or consider Sanders' claim that it would be better to raise the minimum wage and spend less on government benefits. He emphasizes that Walmart could take a hit in profits to pay its employees more. It's unclear to what degree that's true (see again previous link), and unclear if there's a practical way for the government to force Walmart to do that, but ignore those issues, it's worth pointing out that you could also just raise taxes on rich people generally to increase benefits for low-wage workers. The idea seems to be that morally, Walmart employees should be primarily Walmart's moral responsibility, and not so much the moral responsibility of the (the more well-off segment of) the population in general.
But the idea that employing someone gives you a general responsibility for their welfare (beyond, say, not tricking them into working for less pay or under worse conditions than you initially promised) is also very odd. It suggests that if you want to be virtuous, you should avoid hiring people, so as to keep your hands clean and avoid the moral contagion that comes with employing low wage workers. Yet such a policy doesn't actually help the people who might want jobs from you. This is not to deny that, plausibly, wealthy onwers of Walmart stock have a moral responsibility to the poor. What's implausible is that non-Walmart stock owners have significantly less responsibility to the poor.
This meme also worries me because I lean towards thinking that the minimum wage isn't a terrible policy but we'd be better off replacing it with guaranteed basic income (or an otherwise more lavish welfare state). And guaranteed basic income could be a really important policy to have as more and more jobs are replaced by automation (again see gwern if that seems crazy to you). I worry that this anti-Walmart meme could lead to an odd left-wing resistance to GBI/more lavish welfare state, since the policy would be branded as a subsidy to Walmart.