I'm probably thinking more in terms of novels in which it is not any one MC's story, but rather, that of many players, all of whom have an equal share in the spotlight. I suppose having separate stories for these characters, all of which somehow tie together in the end, is one way of doing this (The Hours is one such book that comes to my mind).
I certainly, for one, believe there is an audience for this type of novel. The tricky part (as I've often found) is being able to successfully describe such a story in a query, without making it sound convoluted. Agents usually like to have some idea of the novel's arc, but where there are multiple arcs, it can get a bit unweildy.