Well I must say that was indeed a fine bite.
As for you comment on what other units do and the trade background composition of their AT expeds I can't really say, all I can use is my personal experience.
Having served on 'the wing' for 6 years I can say yes, it riled me when I managed to grab a quick scan of one of the RAF propaganda mags and saw folk sipping wine in the south of France etc but I can't say I ever noticed a huge proportion of those being from 'blunty' backgrounds. In fact I never really noticed any trades mentioned, unless it was an individual who was being reported on.