Untranslated-foreign is a defect

I have just finished reading Stevie Smith's "The Novel on Yellow Paper" - which ended badly in a narrative sense - but also because she kept inserting chunks of untranslated German. 

A couple of weeks ago I was reading Owen Barfield's "Saving the Appearances" and he peppered the text with bits of untranslated Latin, and even several passages in Classical Greek (with the Greek letters, and all).

Both books were mid-20th Century, by authors born around 1900; and both authors will have known perfectly well that very few (and a tiny percentage) of their readers will have been able to understand these foreign bits - so what good reason could they have for including them?  

The answer is (to quote Nigel Tufnel in Spinal Tap) none good reason. 

There are plenty of bad reasons for deliberately using language that you know most other people will-not and (esp. before Google translate) can-not understand, but none are good. 

Back in the day when I wrote in the mass media for a general audience, I knew better than to include sheets of technical language from psychiatry, biochemistry, or statistics - even if incomprehensible jargon might impress some people. 

Plus; it's not as if knowing one or a few foreign languages out of the thousands of them, is even intelligence correlated - there are shoals of fluent tri-lingual people (even in Britain, in this city, here and now) of significantly below-average IQ and without educational attainments. 

I'm afraid usage of untranslated-foreign is an unintentionally-revealing personality flaw; so I suppose I ought to try and be sympathetic; instead of becoming overwhelmed with irritation and hurling the book across the room.