this is interesting and relevant, just got this in physical mail >
https://enroll.amexnetwork.com/US/en/FourSeasonsMR/
"Eligible Card" is a valid American Express Card issued in the U.S.
stay at any participating Four Seasons Hotel in the U.S. and spend $1,000 or more in a single transaction between 10/14/2013 and 12/20/2013
Get 5 extra Membership Rewards points for each dollar you spend on all charges to your room, including your room rate, up to a maximum of 5,000 points
register any Membership Rewards program–eligible American Express Card on this page between 10/14/13 and 12/20/13. You may register more than one Card
Reservations made through travel agencies will not be eligible. Gift Card purchases are excluded
this could be FS running a test
i guess a test for amex too in terms of business deals with FS
amex at one point had redemptions for some FS stays. now only gift cards.