Some of the chains have good security.

I know one German retailer from their storage warehouse point of view (not from the actual stores!). I made the operating system of fork lift terminals and visited quite a lot of their warehouses. And inside their warehouse there is zero connection possible to the internet, they are completely shielded. Their firewall ONLY allows connection to their (locally running) warehouse software.

A warehouse usually have LOTS of outdated equipment, security wise. Barcode label printers 15+ years without any firmware update. Voice dictation systems based on Windows XP. Things like that ... but as they closed down any contact to and from these systems to the outside, this is of little interest to them.