Yeah, I never quite understood why that would be so important to someone so much so that they'd be rude like that. It could be a reflex like mine when people are speaking to me. I correct the "Fewer/Less", "Who/m", "Was/Were" a lot among other things because it is grating on my ears to hear really general mistakes like that. It is actually distracting to me. Oh, but I don't do that to strangers. I only drive loved ones crazy with this.
That's for sure!