In the early 1970s when this advertisement appeared in Commercial Motor there were far fewer cars on our roads. The 'spy-in-the-cab' had yet to be introduced, smoking was still a perfectly safe and legal pastime, motorway services didn't charge over two quid for a cup of crap coffee and bacon sandwiches didn't come with government health warnings. It's no wonder they look happy! I suppose the Volvo does deserve some credit too.