I always assumed this was a purely Aussie phenomenon, but I guess it makes sense that it's more of an "informal speech" thing than a regional ism.
There'a s few other examples but that's the one that always stood out to me
The actual name of the company is J Sainsbury plc.
It started as "J Sainsbury" with no apostrophe s. Then it changed it registered as "J. Sainsbury Limited" in 1922, again no 's.
"John Sainsbury's supermarket" was only contracted and picked up much later for marketing.