This one hs the benefit of being nearly impossible to verify, unlike the waitress one, where it could be checked by several bank/credit card companies.

It was on a seat, someone could always say someone put it there, that they didn't write it. It will always be a he said/she said debate. After the waitress thing I'm suspicious also, but at least this pilot has worked for that company for years, and sounds like she might have a more truthful history.

My other thought is that it could be a prank from the flight crew and meant in jest, which the pilot didn't find amusing. as aren't they more likely to find it than the pilot? And they'd certainly have plenty of opportunity to place it if it were a joke. In this age of connectivity and viral sensation, things like this become international news so fast that its a self perpetuating thing.

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