It is sometimes mistakenly assumed that "experimental" writers (and the critics who champion them) have little regard for the kind of fiction that preceded them, that they simply deny the continued aesthetic value of what has come before. But I think most experimental or unconventional writers have a relationship to the past that is captured by these words from John Dewey in Art as Experience:
When the old has not been incorporated, the outcome is merely eccentricity. But great original artists take a tradition into themselves. They have not shunned it but digested it. Then the very conflict set up between it and what is new in themselves and in their environment creates the tension that demands a new mode of expression.
Writers like William Gass or John Barth or Robert Coover have always been at pains to make clear they consider their own work to be extensions of past practice, part of the very tradition their fiction otherwise seems to be challenging. Barth especially found inspiration for his "postmodern" work in such 18th century forms as the picaresque and epistolary novel, as well as in Greek and Arabic literature, while Gass's essays frequently pay tribute to writers of the past. By "digesting" literary history, these writers both nourish their own talents by heightening the "conflict set up between [tradition] and what is new in themselves," thereby discovering "a new mode of expression," and help to bring a usable literary past into the present. This is not so much Harold Bloom's "anxiety of influence" as it is a necessary sounding of literary tradition in order to find one's own proper place within it.
Certainly there are "eccentric" writers whose work seems merely strange, even incomprehensible, because an enabling context--to what convention is this device responding, to meet what known goal has that strategy been used--is missing. Such works lack the "tension" Dewey speaks of, and the effort to read them is mostly frustrating rather than creatively challenging. But I would guess that most writers of innovative fiction set out to create fiction as good as that which they've admired as readers. To do so requires more than imitation. It requires finding the means adequate to "a new mode of expression" that perhaps will measure up to those already to be found in the great works of the past. Ultimately it requires an effort equal to that Dewey ascribes to the "great innovators in modern painting," who "were more assiduous students of the pictures of the past than were the imitators who set the contemporary fashion."