Christ, that’s awful Gladders. Thankfully I scrapped my account with them years ago, I will not be tempted back.
Another point I would make about the disparity between shops and online is that most people simply don’t care. The price sensitive folk will go online where they want you. Once a year punters are happy if they can walk in to the shop this morning with a score and collect enough for a few pints and a takeaway on the way home.
Short of legislating to make it illegal I don’t see what you can do and good luck finding enough people to make that happen.