What if the Earth is just an aquatic theme park?

The fact that 70% of the planet is water, with most of that being unhabitable for humans, it makes me think that the Earth is just a theme park. The land is like the main walkways. The ocean is like a big pool. What if this planet was just created by some intelligent alien civilization who wanted to create an aquatic theme park? This planet is full of aquatic life. Many of the land animals have a connection to water too. What if this entire planet was just a really really big aquatic theme park?