Why does Johnny Depp only play nonsense characters these days?

Lately he's been in alot babyish movies like Rango, Pirates Of The Caribbean, Alice In Wonderland, Sweeney Todd, Willy Wonka...all being really quirky fantasy characters. So why does he waste his talent on crap like that? Or is that all he is being offered? If so it's a shame, because he is a very good actor!