You know what? Screw parallaxes. Assume for a moment that you're on a boat, 50 miles offshore from a mountain. It has been observed (don't even try to turn this into a conspiracy, I've seen it), that as you approach the mountain, it is partially obscured, but as you get closer and closer, it is less and less obscured. When you're closer to shore, you can see the bottom.
Answer me this: why does this happen? Assuming the Earth is flat (indirect proof olol), your line of sight, even at a distance, should show the bottom of the mountain. But that's not the case.