>>717647221American fantasy developed independently until the 1960s-1970s, because Tolkien's works were in publisher limbo over here.
From REH and Lovecraft's circle, to guys like Vance and Leiber and past them, the US fantasy market developed in their own direction. With a greater focus on action and an acceptance of a motley mix of 'things' in a world. Where sci-fi lost tech was allowed to exist beside guys in chain mail swinging maces at one another, alongside shit like dinosaurs or cryptids. This was all together fantasy, and being internally consistent was not important.
Gygax was more of a fan of the American sword and sorcery fantasy than he was a fan of Tolkien's work. But his buddies were fans of Tolkien, so he threw references to him into his more American table top game.