Years later, after leaving the Service, I was surprised to find that De H's at Hatfield had no less than 5 Dining Rooms, called "Messes", all segregated into sections for tradesmen, middle and senior management.
I was once a "young industrial chemist" and in my experience companies engaged in aeronautical work (e.g. Dowty Rotol) were far worse for this kind of segregation. I had always assumed it was because they worked closely with the RAF and MoD.
When the British class ridden disease came to company cars it was ridiculous and the motor industry exploited it perfectly.