I don't know . I had a cart full of everything from window blinds to steaks and for me it seemed like an ordeal because its an unknown.

And let's be fair, it's not a matter of scanning and moving on, that would be easy. Each item has to be scanned one at a time, and then weighed and bagged. Takes forever and in my experience something always goes wrong and I get "please wait for cashier / assistance".

Maybe just bad experiences or I am perhaps an idiot when it comes to them.

To the point of the topic: keeping my head down while someone scans my items and then swiping my card is far easier than all the attention and interactions I create with the self checkout machines.