Personally, I find a latex resume comes across as pretentious if it's your only latex publication, which is usually easy to determine from its contents.
Taking a simple task like writing a document in Word and using it as an excuse to learn a text formatting language sounds perfectly reasonable for a hacker.
pretentious, adj. Attempting to impress by affecting greater importance, talent, culture, etc., than is actually possessed
Learning latex because you're curious is one thing. Using latex on your resume solely to give the impression you know latex would qualify as "affecting greater talent than is actually possessed".It's cynical and utterly baseless to deduce "pretentious" motives.
McGee explicitly mentions that the reason he does it in LaTeX is not to get the "+12 points bonus". I think you're being presumptuous in accusing others of being pretentious for using LaTeX.