Crucial Childhood Questions #1: Why do Toddlers put food in their hair?

Common feeding problems
Food, as most people are aware, should go in the mouth. Seems logical?
Not for toddlers.
OK, so a self-feeding toddler may go slightly awry in the target area. There may be a few dribbles down the chin, a bit splashed on the bib, maybe even a stain or two on the cheeks but that's it, right?
Not for toddlers.
Oh sorry, missed out the hands. Yes, there will be a bit of grease and grime on the fingers - of course there will be, toddlers don't use a knife and fork. But that really is it. Correct?
Not for toddlers.

Signs to look out for
It's when you look at your child's scalp and think for a split second that they have really bad dandruff. (That's the remains of the sponge cake from tea time.)
It's when you pat them on the topknot and find that their head is armour-plated, just as though they'd gone massively overboard on the hair gel. (That's a few leftovers from the lunchtime honey sandwich.)
It's when you look a bit closer and find that they've also got yellow highlights. (That's lemon curd.)

It's when you see all those things that you remember that when it comes to toddlers food can go anywhere, including in their hair. (That's right.)

Why is this? 
Why is it that in between mouthfuls a toddler will rub both hands firmly against his or her head, smearing sticky substances into the back hairs? When it comes to using spoons they have even more scope: muesli in the fringe, yoghurt on the eyebrow, porridge just above the ears, there's no real limit to their range with spoon in hand. Sometimes the attendant adult may find a few dollops flying in their direction too which is why quick reflexes are such an important part of parenthood.
As to why they do it, I don't really know. Natural fidgetiness, I suppose.

How can it be stopped?
It can't. Not for a long time anyway. Accept it as an unavoidable and occasionally amusing part of growing up, move on with your life and keep a damp cloth handy.

Thank you
...for taking the time to read this article. If you have any further concerns - i.e. something that looks like blood just behind the right ear - don't worry: it'll only be strawberry jam.