Box or Toy?

The best classic toys are sometimes not designed as toys.  Take your basic cardboard box.  One memorable Christmas my youngest sister (#3), aged 2 at the time, had the most fun opening her presents ever.  She emptied gifts from their containers and played ecstatically with the box.  She appropriated all of our boxes and never looked at the toys they contained.

She wasn't the only one of our tribe to find happiness in the box, not the contents.  Here''s another of my sisters (Sandy? Carol?) loving a cardboard box under the Christmas tree.

The first Best Loved Grandson went through a time when he was about two years old when his favorite pastime was playing with a large box that he had decided was his "truck".  When he started to pretend the box was his truck, Mom and Dad drew a dashboard on the box flap with crayon and the box became officially his favorite toy.   He would carry around a set of plastic teething keys in his pocket when he wasn't in the "truck", just like his parents did.  To make the scene even more real, his Daddy drove an old truck that needed a screwdriver to start it (the ignition had been drilled out at some time) so BLGrandson carried his keys, but kept a plastic screwdriver in the box so he could "start" his truck.

I found this that is supposed to attach to a box to make a toy.

Rolobox via Odeedho

 What do you think?  Would this have made our BLGrand's truck better? Or does a kid need it? Should we defend the purity of the cardboard box?