See I was thinking that at first too. But then the supermarket has to host the software to manage the devices. If it were just fridges, fine, but surely it is a ton of things, all with their own software… so letting the fridge talk directly to the companies servers saves the supermarket from needing to have serious IT staff. Now there are a ton of ways to make it a safer connection so that it can’t be hacked so easily. From the sounds of things, even that was too much for the supermarket people to do. So default password it was.