Snipers take into account Earths Rotation but Airplane Pilots Don't need too?

So a sniper takes into account the earths rotation for a bullet travelling in the air for all of a second or so but earths rotation has no effect on airplanes travelling for hours? Please explain why one is affected while the other is not, lol! I know about the "cocoon effect", and if that were true it would have to be applied to the bullet as well as the plane, Earth is Flat Suckez!