Dispensers cannot dispense Jack O' Lanterns to create snow/iron golems even though the player can

Build a snow golem and use a jack o' lantern to spawn him, it works. Try the same thing but with a dispenser dispensing a jack o' lantern to spawn him. The dispenser just shoots out the jack o' lantern instead instead of spawning a snow golem, when it does work with normal carved pumpkins.