@ajroach42 that has come all the way from Britain; Crusha is a flavoured milk additive (still available today).
Unigate experimented in the 70s/80s with printing these ads on the milk bottles that the milkman delivered. They didn't always have these adverts, and they were more common around holiday periods (maybe as kids were encouraged to bring in the milk and they would see the ads...)
@ajroach42 others had mostly milk-related ads for cornflakes, tea, biscuits, newspapers or the dairies themselves but occasionally there were even ads for car dealerships on them.
The milko still delivers round my street, he has a new modern electric van and the same milk bottle design is making a resurgence (currently without adverts, though I wouldn't rule out their return if/when the bottom falls out of the internet adtech market!)
The social network of the future: No ads, no corporate surveillance, ethical design, and decentralization! Own your data with Mastodon!