They also have a tasting 4-5 times a day at the Rose & Crown sponsored by InBev - nothing novel though (Beck's Light, Stella, Bass etc). You need to get a token from the CM and get in line for this. They put four bottles on each table (which seats four).
Also, there is the Sam Adams seminar at the American Pavilion that gives 4-5 small samples and a nice bottle opener keychain giveaway.
That's about it.
They do have the Hops and Barley stand which carries about 10 Sam Adams beers at the American Pavilion - always worth a stop.