I believe you. I don't know you from anywhere except this thread but most mis-quoters are not malicious fabricators so the numbers are on your side. There's more than one compendium of fake quotes
and lots of quote-checking websites. For the Keynes fabricated quote only the bad grammar should have warned you I think, even if you never read anything of his. Since it's untraceable to whomever made it up there's no telling if he was someone trying to convey his own "sentiment" on capitalism or someone wanting to disgrace Keynesian economics. The first book has a notice to readers to mail in fake quotes to the author in case of a new edition. I don't know if it's worth doing, I've never done it myself.