Aaron, while I don't subscribe to the notion of cultural 'advance,'
there have been non-grain-based cultures with many features of civilized
(town/city-dwelling) cultures-- slavery, organized religions with
intricate rituals, wars, all those advanced things.
For starters, cultures of the Northwest Coast of N America come to
mind. They're well documented, even in film, and had wonderful winter
theater; Europeans thought they were cannibals because of their
Cannibal Society, active in winter... but then, Chinese used to think
Europeans were cannibals... and in a nonliteral sense, they were. Pet