Don't know about any connection btwn Aldi and Trader Joes? Thats news to me.
Yeah, the family that owns Aldi bought it in the 1960's. My understanding is that it's somewhat like a less vicious Adidas/Puma type squabble, were each brother got control over a portion of the company. In America, one branch of the family has Trader Joe's, the other has Aldi. In other places, they just split the Aldi name.
Aldi for me has always been a conditional supermarket, here in the NE, they tend to be in more out of the way places. I will make a special trip for certain things like ham, certain sweets, etc....
I have nothing but kind words for Trader Joe's, never a bad experience there. In Ny, Trader Joe's is sort of considered a better middle class supermarket. Cheaper and slightly less ritzy than Whole Foods, Fairway, etc.... But not as bad as the majors like Pathmark, etc....