I'm a member and it's the first time I've heard that. Former riders who were members could get a Gold Card for an exta £5 which allowed them free entry if they were accompanied by a full paying adult but it was scrapped.
I would have accepted a Monday delivery every week, but getting previous week's one on a Wednesday and then getting the following one on the Thursday was too much.
I cancelled my subscription a few years ago due to erratic deliveries, ASDA next to me have it occasionally Morrisons usually have it but that would mean almost a five mile round trip.