The true answer

The moon is also flat.

Why do people think it's round? [spoiler]It's clearly a cube.[/spoiler]

I think about this myself. I believe part of it stems from a lack of meaning or purpose that people mistakenly think that science forces upon the world. If you can "explain" everything in material terms, then reality looses a sort of "magical" charm, or essence, that believing supernatural realities imbues it with. I can attest to this. Having once believed fully in a 10,000 year old earth and rejection of evolution, my belief that God created reality gave my view of nature a sort of semi mystic charm similar to the feeling you get from fantasies like Lord of The Rings. Except to me, that charm was literally real. The universe really had a deep intrinsic purpose and mystery rooted in the fact of existence. When I began to accept evolution and the material authority of science, that charm withered for me. I still believe the universe was created, and that God exits and interacts with us on a spiritual and rational level. But I dont think He has micromanaged every step of creation. I think He created the universe with material laws, and that life emerged through the operation of those laws without divine intervention. Or if divine intervention happened, by the very fact of such intervention being divine, we will never find evidence of it. Thus, using "evidence" to argue for God's existence is a theological and philosophical dead end. But thats me. I think people believe flat earth because such belief restores a sense of wonder (in their minds) and ineffable essence to the question of ultimate meaning. People have a need for the divine, a thirst, almost. But today they try to quench that thirst with all the wrong things. Flat earth, creationism, new age, conspiracies - any idea that can support the existence of wonder in nature, while being beyond the critical reach of scientific inquiry. What they forget is that science complements the existence of divine wonder as much, if not more so than bogus theories and intellectual denial...

[quote]When did this even start happening?[/quote] Because all evidence you can observe yourself says it is

I believe it all stemmed from the "fake moon landings conspiracy"

Because they’re a bunch of idiots with access to the internet. [spoiler]random fact: more people believe the earth is flat nowadays, compared to the middle (dark) ages.[/spoiler]

It’s the human mind and it’s want & need for challenge, the shitty part about science and it’s irrefutable evidence; especially after the fact, like when the world is proven to be round, when evolution is proven to be real. And it’s often challenged by ludicrous and often idiotic beliefs.

it has to be flat in order for it to stay on the space turtle. it's just science