(06 Jul 2021, 9:38 am)streetdeckfan wrote Only recently have they started doing that. It used to just be £1 to check if the card was active

Asda started a few years back. Quickly pulled it after a  backlash.
Costco have been doing it for a while too.

Either way, it makes sense to ringfence closer to the actual amount and not a difference of 90% as has been suggested could be the case at GNE Towers.