Unless there was a very expensive item out of sight, she was ripped off even worse than by Chartwell - that's not even a good fivers worth now, let alone 20 years ago!
I think that Asda priced shopping list is a tad optimistic - and we don't know the exact quantities/weights, etc., but anybody charging thirty quid for that is taking the p1ss. OK, there is packaging and deliver t take into account - but even then thirty quid is still taking the p1ss!
Get stuck...