Well it's being done all over the place... Germany, UK, France, Italy... Sitting with engines running for sometimes 30-45 minutes waiting for slot time makes little sense.
And no, it was not about moving from "one stand to another" it was about moving from a gate to a parking position.
From the article:
It’s understood it was being towed away from a passenger boarding air bridge by the truck in a ‘pushback’ manoeuvre ahead of take-off when the smash occurred.