The drummer insists he doesn't have extravagant tastes, and prefers to use his money to further his passion for music and literature.
Watts reveals he owns a collection of rare, signed first-edition books by authors including Agatha Christie and Evelyn Waugh, and he has also bought drum kits which were used by some of his favourite musicians.
He tells Britain's The Guardian, "I collect jazz mostly. Drum kits as well. I've got one of Kenny Clarke's drum kits that he gave to Max Roach - I bought it off his widow. I have Duke Ellington's, the famous Sonny Greer drum kit, it's fantastic. Big Sid Catlett, one of the great 30s swing drummers, one of his...
"And books. Not antiquarian books. Signed first editions of mostly 20th century writers. Agatha Christie: I've got every book she wrote in paperback. Graham Greene, I have all of them. Evelyn Waugh, he's another one. (P.G.) Wodehouse: everything he wrote."