To be fair:
I think pointing out a grammatical error is fine. That can be constructive, especially if the message is being heard by thousands of potential customers. If I were Pete, I'd want to know.
Also, proper grammar IS important in non-colloquial settings. Whether we like it or not, people judge us by the way we speak, the words we use. Sure.
HOWEVER, referring to LSC's customers as 'semi-illiterate' is... well, offensive to say the least!! (as well as wholly inaccurate)
