Because a massive bug drunk a ton of Coronas, turning into a deadly bug, and is now rampaging all across the world in its drunken state, killing and injuring millions of people.
How much would a woodchuck chuck if a woodchuck could chuck wood?
Because the first orange ever really liked the orange color, so it spontaneously changed its color to orange, and then, all of its children inherited its colors, and are like this up to this day