You mean like the EPA sticker on a new Volvo?

Wasn't the danger of encountering devices (somehow) programmed to act differently in a regulator's test regime than in daily use one of the points made in the article? (Actually achieving this in the gas pump situation is left as an exercise to the reader.)

I don't know about that - all that proves is that the pump hasn't been opened since inspected. While I suspect even that isn't foolproof, there's nothing stopping someone from modifying the pump through external means, whether through a remote firmware update or mechanical means, like a magnet placed on the outside of the pump that engages some hidden mechanism.