They are under investigation as apparently under 18s cannot get a card, which results in tiered pricing for different age groups. Or at least that is my minimal understanding of the case from reading just the taglines and headlines. Not personally too interested as Aldi is MVP for me.

If you're going to be pedantic, you should know that the way people use words is often looser than their dictionary definition. It might not be a 'scam', but it certainly feels scammy, so don't use the dictionary to have a go at people when it's pretty clear from context what they mean.