Why does Walmart lobby for increasing the minimum wage?

It’s because they already pay at a rate that is above the minimum. Increasing the minimum wage reduces competition because it increases the “entry” cost to other new and existing retailers. This, if it happened, would produce a small oligopoly (minor monopoly) over the market and reduce competition further – to Walmart’s benefit. Once an oligopoly or a monopoly have taken their course, competition is null and the seller controls the pricing. Rather than in a purely competitive marketplace where the buyer and seller “agree” to some (the equilibrium) price. Effectively making it worse for the poor folk if Walmart had it’s way and was the only player on the block.

From the flip side though, Walmart creates a benefit to the poor by having ridiculously low prices that are well below the equilibrium level. In fact, the net benefit of them having such low prices is more than enough to make up for the lack-lustre labour benefits that they provide to their own employees (but that’s another argument entirely)

So, love it or hate it. Walmart is both a demon and a saint.

The duality is charming, actually.