This is Monthy Python at its best! No holds barred (anything goes), bizzare and making fun of the pretentious middle/upper class.

All in one (gross) package!

If it’s no holds barred in the sketch,the funny thing (if you look at the full version) is the “holding back” that both the guests and the staff at the restaurant do, just not to offend the all important, VIP, filthy rich, very regular guest Mr Creosote, even to the point of themselves throwing up!

Gross, yes, but you would have to be a braindead zombie if you don’t find anything in this sketch funny(as some commenters).
And the mint wafer self-combustion at the end is just a classic laugh explosion!

Love how John dives for the trenches(like the tiny mint was a hand grenade).

The regular guest “MR Creosote” problem solved for the restaurant in the most devious way possible.

The first time I saw it I just died with laughter.

Genius!