He signs c/o the San Francisco Giants for a $20 donation for autism research or something related.
He used to sign for free through the past 5-6 years - but must have just had enough signing without getting something in return.
I think it's just a generic postcard someone had Damon sign at a game - then someone got creative and stuck the card on the postcard, so he or she would remember who it was signed by.
I got duped on ebay bidding on a 1989 Topps Traded Ken Griffey card - didn't even occur to me to give the checklist a look and see that both father and son were in the set.
I don't think Hamilton's family has to worry about money and it doesn't matter - people are still gonna pray for him regardless of whether or not he's a selfish ***** that looks like he's destroyed his career again.
I don't like browsing for stuff I'll never come close to owning in my collecting lifetime, but thanks for pointing this out - the catalog will be great reading material to look at the pics / read the descriptions to pass the time.