Beware everyone,
Just found out that in order to earn any Marriott Rewards points, that it can only be for me personally, checking in and paying for the stay personally. I set up a stay at the San Francisco Marriott for my wife using the on-line reservation system. When the bill was emailed to me, I found that they had removed my Marriott Rewards account number. Upon making a missing stay request, I was told that no family or friends stays earn points. So presumably, there is only value in setting up a rewards stay for her. If I'm paying, then there's no incentive at all to stay at a Marriott. This is news to me.