I my country, it's been over for about 5 yrs. First I could get a battery hand-scanner when entering the shop, scan the items as I put them in my bag, and the just flash a barcode and pay at the self-checkout. Nowadays, I launch my store app, scan barcodes directly w/ my phone, and when I'm done just select "Pay" and walk out.

Occasional audits apply, about every 10-20 shopping trips I've got to let them check I indeed scanned 2-3 items. Total re-scan about twice a year.