
From the other side...
I was convinced I was being spammed when I attempted to make a web-booking of a Best Western chain hotel in Italy recently...
Having passed through the web payment scheme (using a credit card) and believing the booking to be complete, I then received an email from the hotel asking for faxed scans of my passport and credit card.
Alarm bells rang.
I was not a happy bunny, given the obvious risks involved, and eventually involved BW corporate - whose conclusion was (a) it was genuine and (b) they didn't have control over local operations - and the CC company, who were less than amused but didn't flag it as fraudulent. The hotel claimed that this was an Italian money-laundering regulation...
We eventually compromised on a scan of my driver's licence, and enjoyed our stay.
Nonetheless, the whole *point* of a web-based credit card payment is that it is complete unto and of itself; the risk is with the CC company if the card is reported stolen. Behaviour like the hotel's, whether government mandated or not, simplifies matters no end for scammers.
(I never liked handing my passport over, either.)