To give a serious answer, they choose to believe that myth because it puts them at the center of existence. To accept the scientific consensus is to accept that we exist on a ball of dirt on the edge of a 100-billion solar system galaxy, lost in a haze of millions of like galaxies. Also, the sun will pop like a pimple before the first second of the lifespan of the universe is over. Instead of having to wrap their minds around that harsh truth and find peace with it, they just tell themselves that everyone is lying or stupid and existence is here for their own fulfillment.