Why is it that every children's keyboard I come across has the most annoying and imagination-inhibiting feature sets-- most notably "demo" or "songs" buttons that play complete sets at the touch of a button?

I can't stand seeing bright, intuitive children sit back and let the machine do the work when they discover the little "song" buttons, so I decided to disable this little keyboard's "demo" buttons.  All that remain now are notes and single-shot sound effects.