[SideburnsOfDoom]

> complete and utter nonsense

I don't think that it's complete nonsense. Or, it is deliberately absurd, but it doesn't come from nowhere. Monty Python debuted in 1969. They often took the mick out of the generation before them, who on the one hand Won the War and saved the country, etc. But who on the other hand by 1969 could also be mocked as aging, uptight, officious, stuck in the past, "we had it tough, you kids have no idea", etc.

So: Spam. It's processed meat in a can, more like a wartime emergency ration than anything else. Fresher foods were in short supply in the UK during and immediately after the war.

The sketch is elements of the Zeitgeist around them then. Which would have also included funny, costumed college musical numbers, from their time in the Cambridge Footlights.