I will say one time I placed a big box to the right of the scanner then scanned it, but the machine vision system had already decided I was trying to sneak that box past the scanning area and flagged me as a potential shoplifter, despite having scanned the item before the vision based anti-theft flagged things and shut down the isle. So Walmart's anti-theft still does flip out on occasion.

Certainly better than the days when every other item would do "unexpected item in bagging area", but still can be obnoxious and the employee acts so suspicious when you trigger it.

Between having about 10x self checkout as manned checkouts, and some bad bagging experiences, I strongly lean toward self checkout, at least if I have a reasonably small amount of stuff. Larger orders I do the "load my car" which is supreme laziness for me and most work from the employees, but don't trust them with perishables and produce.