And the scanner to exit is terrible for fire safety and accessibility. Also I've seen it break with the result that you had to trigger the alarm to leave.
It does not work smoothly at all, but perhaps you live in a different sweden than I.
I use this method of shopping whenever available.
And for items like bread or so you need to navigate a number of menus to find it.
And of course you are asked if you are a member, if you'd like to become a member, if you want to do a donation, and a number of other useless questions.
Yes you do need to be a member to use the system, but that's a very small price to pay for the convenience and speed of avoiding all lines and stress of the regular checkout.
Going from "a supermarket near my home" to "every single supermarket in sweden" is kinda of a big leap.
Try ICA in Olskroken or Godhemsgatan for example…
I Most supermarkets have self checkout, but even that isn't omnipresent (and it's usually slower).
The other problem is that, like self checkout, it often requires human intervention (buying alcohol or high value items, for examples) still requires human intervention. This can require a long wait at the end. I once got so sick of waiting that I left my shopping and walked away and went somewhere else.
Instead of a guard there's a scanner by the exit gate where you scan your ticket. In my case just a small stub since the actual ticket is sent digitally.
I think it works so smoothly, much better than before this system was introduced. My recent experience buying groceries in Belgium was very similar.