We communicate in different ways with different people at different times.
If I am writing a leaflet for general consumption I keep the language clear and simple, leaving very little room for ambiguity.
If I am discussing computing with colleagues it is likely that the conversation will include technical language that wouldn't be used elsewhere. A group of people who had all studied, say History of Art, English Literature or Astrophysics would have another set of technical terms.
In a group like this we talk about words. One would expect to cover the whole range from the simple to the unpronounceable.
The "showing off" bit comes in when we choose to use inappropriately complex language in a situation where we know it will be perceived as being used to score points. In these days of inverted snobbery more people make their language downwardly mobile rather than the converse.
One of the things that I always found strange was that words from the study of literature, history or French would be considered as essential knowledge for an "educated" person. Whereas it would be possible to know everything there is to know about DNA, Quantum Theory or nuclear fusion and have very little to talk about at a party.
As science becomes the new "arts" with so much popular writing about science perhaps it will change. Somehow I'm not so sure.
