Bad Customer Service:
ALDI is fine as far as it goes. Prices really are lower, and the quality is usually as good as anything out there.
Where ALDI falls down is on customer service. In the best of stores, there will occasionally be an issue, and you'll want to talk with a manager, or possibly Corporate's customer service people.
In the case of ALDI, this is absolutely fruitless. You are always told that ALDI does what it does the way it does for its own reasons, and that it will not change. Trying to comment on a favorite item getting dropped, or a poor selection in one area, or a change in product quality, gets you absolutely nowhere. ALDI figures it has everything figured out so well that input from consumers is not only unnecessary, but unwelcome. There is actually a rumor (the truth of which I do not know), that ALDI's operations manual for stores discourages employees from conversing with customers, as a waste of time that might be put to "better" use elsewhere.
This corporate culture can have some weird results, as when the mayonnaise in our area's ALDI's went from perfectly fine to a strange, runny concoction that tasted absolutely awful. Weeks and weeks and weeks went by, with no change; we customers were told it was "a new supplier," and that "there's nothing we can do about it."
Only after returned, partially (and scarcely) used jars of the stuff piled up and refunds under the ALDI guarantee became too great to ignore, did someone work on the problem. Total time, something like four months - for an issue any company that listened to consumers could have fixed in fairly short order.
Oddly, the "company line" and the unfriendliness increase as you go up the food chain, not decrease, as with most well-run companies. I recently had a run-in with Corporate that left me so cold I'm not sure if I'm ever going back or not. The person I dealt with was so unprofessional and nasty it was not funny.
So, that would be my comment -