Actually a fun fact there, they're both owned by different Aldis.

[Aldi] was split into two separate groups in 1960 that later became Aldi Nord (initially Northern West Germany), headquartered in Essen, and Aldi Süd (initially Southern West Germany), headquartered in neighbouring Mülheim

The brothers split the company in 1960, reportedly over a dispute about whether they should sell cigarettes. Karl believed they would attract shoplifters, while his brother, Theo, did not. This led to Theo running Aldi Nord and Karl running Aldi Süd.[22]

in 1976, Aldi Süd opened its first store in the United States in Iowa,[a][29][30] and, in 1979, Aldi Nord acquired Trader Joe's.[19]

https://en.m.wikipedia.org/wiki/Aldi

Then it's an extra asshole move not to let cashiers at Trader Joe's sit because they already know the benefits of that from the Aldi chain