Back to the regular flat earth, what keeps the water from falling off of the edge?
Q: "Why doesn't water run off the Earth?"
A: There is a vast "ice wall" that keeps the water where it is.
Quoting the archaic FAQ this is the case.
I'm also fairly curious about the OP, if people would stop beating around the bush. All things in nature exist for a reason, nothing just happens. The ocean is necessary in order to hydrate the earth, the ocean is kept clean by the creatures that live in the oceanic ecosystem, hence the coral reeves etc. is also necessary.
Plants are necessary in order to sustain life and purify air, Brazil is necessary to sustain tired humans with coffee in the morning.
The ice-wall has its purpose of containing water on the earth, or so the FAQ says.
What I'm more curious about is, why would the governments want to hide the existence of such a wall? Sure enough I know that being able to forge information equals control of the general populace, however, what control can possibly be attained by hiding from people that the earth is flat?