I have no Idea Why Will is doing this???

A couple of days ago, Will started doing something very strange and I can't for the life of me figure out why. Every time he eats, he puts his food on his head! Isn't that weird. It's so hard not to laugh. Paul and I try to be serious and tell him not to do that, but we take one look at him and start laughing and then he's laughing which of course encourages him to do it again.