Those of us who grew up in the 50's, 60's or 70's know that a fun part of breakfast cereal was the free prize inside many boxes. This was a marketing ploy that really worked, drawing in kids and sometimes adults to get a small toy, sports card, etc.
Hopefully this will see more free prizes in cereal boxes. I'm not sure why they ever went out of fashion. Perhaps it was an extra cost companies didn't want to absorb, or maybe they felt consumers were too sophisticated. But, at a time when cereal companies have to innovate to stand out this could be a winning strategy for the industry and for children building memories with little plastic toys.