You may get an irrational sense of annoyance from reading his writing style, but to tell the author that is pointless.
What I think of their writing is irrelevant, if the OP wants to write like that what on Earth is the problem?
It may or may not be that he or she sounds to some as if they are deliberately trying to make himself sound posher than he or she is in order to put people down, but having read the OP's responses I genuinely don't think that is the case (although perhaps I'm wrong, of course). I think there's something wrong with criticising him/her when he/she had no intention of offending anyone.
If we were to penalise someone for using this flamboyant language when it's simply the way that they've been educated, isn't that just as bad as discriminating against someone for talking in, for instance, a regional dialect or a camp way?