No no no
"come on folks, fool me once, shame on you, fool me once..."
He was not offering it as a quote. Its like if you saying this to someone you were talking to. If you were talking to someone this is how you would say it:
"come on Charles, fool me once, shame on him, fool me twice, shame is on you"
If he was offering it as a quote he should have included a semi-colon. He was addressing you as an audience, he was not talking to me personally. So if you are fooled once, the shame is definitely not on you (the folks)
My quote offered was from my perspective, although admittedly i screwed up the beginning...i meant to say "fool you once, shame on me".
Eitherway, his rendition was wrong. He was addressing someone other than the fooler so using "you" was VERY INAPPROPRIATE.