One thing that could help a lot is trying to get the receipt data from some loyalty card some shops have. In Romania, almost all big stores have mobile apps wh

One thing that could help a lot is trying to get the receipt data from some loyalty card some shops have. In Romania, almost all big stores have mobile apps which allow you to export your purchase lists. Granted, some of them have dumb outputs (Lidl give you an image of your receipt, so you still have to do OCR on it, Carrefour gives you a PDF), but it does make the problem much easier. Of course, this won't work for your random corner shop.