You think the managers at Aldi work for the satisfying feeling of serving their community or what? Aldi cut costs in any way possible and greeters are simply a very visible way.

Aldi isn’t really a direct competitor of Walmart. There are other more similar (hypermarket) chains in Germany that directly offered the same as Walmart. For its attempt to enter the german market, Walmart bought up a bankrupt chain of such hypermarkets. The stores were in worse locations than those of their competitors. Basically, it was unwanted left-overs. The Walmart, closest to me, was right next to its competitors but on the far side. It was just a little less convenient. If they had been able to offer better prices or quality, that might have made it worth it. But they couldn’t. There were only greeters and packagers.