One element of this seems to be a tendency to make explicit words or phrases whose meaning is not immediately apparent. Look at the use of acronyms too: ATM machine (Automatic Teller Machine machine) ISBN number International Standard Book Number number) SCUBA gear (Self Contained Breathing Apparatus gear)

The ISBN example is one where anyone using the acronym knows exactly what it stands for, yet there's still a tendency to add the 'number' at the end.

I think of this as something like a weak force in language.