My brother almost got scammed 3,000 baht right in the airport.
Cashed in $500 USD. (Roughly 15,000 baht at that time)
He found it very odd that the teller was giving him all 500 baht notes instead of 1000 baht notes. He counted it in front of her. 12,000 baht and some change.
$3,000 short of what he was owed.
Typical scam. Always do the math yourself and count your money!