Montreal did this by restricting the number of people who could work at the grocery store after certain hours especially on weekends. This would increase line lengths and drive people to dépanneurs.
It was also pro-worker, which Quebec has always been.
Of course, not everything is available at deps, and not everyone shops during the day so it was a pain in the ass if you had a big shop to do.
Not sure whether this is still in okay, but I’ve noticed local deps are more expensive.
Great book, was surprised the article wasn’t from the same era.
Now I’ll have to re-read it.