@ravelin first of all, I don't have to encounter examples of something very often for that something to be worthy of having a term refer to that. I have never encountered a platypus, and yet it makes sense to reserve the term "platypus" for it.
Secondly, it often makes sense to have separate terms for two things even if the two terms might mostly overlap. For a very long time "aircraft" and "airplanes" were basically overlapping.
And finally, I think misinformation can be intentional…