What sort of hungers do the Great Old Ones have?
Lovecraft described some of his creations in great detail. Others are described in ways that are give the reader a vague sense of the thing and leave the specifics to his/her imagination. And others are left as vague eldritch monstrosities, barely comprehensible to the human mind. Shub Niggurath is one of those. So she (it) can be depicted however seems most appropriate.