We can lay some blame on either MK or whoever the team is that worked on the Florida version of the ride. Their Splash doesn't fit Frontierland either, though they tried and did well enough I suppose that it doesn't register for most people. I don't know if it was ever considered or not, but WDW's is the only version without a Critter Country of any kind, with Tokyo purpose-building an area from scratch that is even situated in such a place that it acts as a transition between Fantasyland and Westernland (as Frontierland is called there).
I would love more insight into their decision-making, frankly.