The first is from AA Gill, who, having dealt with letter writers who have nothing better to do than to darken his door by complaining about supposed improprieties in his grammar, shoots back:

“I love the rabid grammarians. You are the Jehovah’s Witnesses of grocery labels. For them, the written and the spoken language are a constant torment of misplaced commas, swallowed vowels, and “uns” usurping “ins”. Oh, the bliss of them. They are utterly redundant. The grammarians’ ire and fury count for naught. They make not the slightest scintilla of difference to the flow of the great torrent of language; they can’t change a single syllable in anyone’s mouth, or reunite the simplest infinitive. I love them, because they so utterly miss the point, comma, semicolon, exclamation mark.”

And, in a quite similar vein, Mike Pope forwarded me this gem from TruePath in a comment at The Volokh Conspiracy:

“[…] if the goal of prescriptivists was just to guard against things some readers find annoying then their primary obligation would be to shut up. No error of grammar can be as annoying as someone who lectures people about their grammar (this is different than genuinely trying to inform someone that most people find something to be poor grammar)”