I had assumed the pronunciation mimics a posh, over-the-top accent, when I read the German version. In it, the name is "Kaffeetrinken". The word "Kaffee" (coffee, if you couldn't tell), has different pronunciations in use, one with a long /e:/, and one with a short /e/, almost a schwa under the breath of the /f/, and various alternative spellings such as "Kaffe", "Café, Cafe" The later is the more common pronunciation for the beverage, but Jonathan Kaffeetrinken insists his name be pronounced "Kaf-feh-trin-ken".
The phonetic spelling first appears when he is served by an attendant (or a valet?), hence an expression of arrogance does seem to fit the character.
I can't explain the difference very well, that would be due on German.SE, but I have no doubt that "common" and "elite" is the intended contrast.
It's possible the translator reinterpreted this, and that I'm missing a joke about the original, but I believe the translation is faithful. I've read or rather listened to a fair share of the original, except for this one, and I don't know the particulars of English Accent, so I cannot answer the question regarding the original pronunciation in due detail.