They've done an awful job of marketing it.

I think discovery is a pretty big inherent problem with the system. Unless you already know about it, to discover it requires that you use the app, and spot the "scan & go" option on the very busy home page

Compare that with handheld scanners that were becoming popular in the Netherlands 5 years ago, which create a visible wall you walk past every time you enter the store. Discovery is obviously much better in that method.

Which I think is why they're switching to these tablets in trolleys. People are going to trolleys anyway. I think it's a shame they're going with big cumbersome tablets rather than a simple handheld scanner that could be used with a basket or when just holding a few items, but oh well.

But you're completely right that they did a fucking terrible job marketing it. There were signs up all through the store, but if I didn't already know what it was I doubt I'd pay them any attention. A TV advertising campaign focused on "the shop of the future" it some such tagline could have gone a long way.