Yep.
While there are a number of major chains in the U.S., for some reason two grocery chains, Deirbergs and Schnucks, have taken the 'premium market' in the St. Louis area. Below those are several other mid-level stores, most notably in my area 'Shop n' Save'. Below that would be ALDI.
I probably do about 70% of my grocery shopping at ALDI, and only go to other stores for name-brand items that I can't get at ALDI. For instance, my husband only drinks Pepsi One soda, which ALDI doesn't carry.
Shopping there is as cheap as if I were very carefully clipping coupons at other places. I'm more than a little shocked that the chain isn't better known.