The buyer and the person who enjoys the product may be different people.
Glico in 1922 was accompanied by a picture card. The history of the company records this device as well as the confectionery itself as an incident at the time of its founding. Riichi was not only dealing with adults who were concerned about nutrition.[2]

Bittercup / Wikimedia Commons / CC BY-SA 4.0
According to the official toy history, toy caskets were introduced in 1929. The idea behind this idea was to view both eating and playing as important activities for children. The composition is such that the enjoyment remains even after the sweets are eaten.[3]
It would be too quick to dismiss this idea as just a giveaway to encourage purchases. The reasons that adults are satisfied with and the reasons that children want may not always match. Even if we explain more about nutrition, children's enjoyment will not increase. On the other hand, enjoyment alone is not enough to satisfy the judgment of the adult purchasing the product.
By putting two values in a box, you can respond to different people with one product. However, if one of them becomes an excuse, the relationship will collapse. The stronger the device is to attract children's attention, the more the quality of the confectionery and the sincerity of the explanation will be questioned. The value of fun is not a license that relieves you of other responsibilities.
Beyond confectionery, Riichi's career includes medicine and alcoholic beverages.[4] I don't want to speculate about what I learned from that experience beyond what is left behind. Still, if you look at new products not in isolation, but in the context of who chooses them, who uses them, and what they expect, you can clearly see the ingenuity of the company's founding.

伝Interpreting YAMATO DENSHI
One box, two sets of expectations.
I'll try to draw the people who decide to buy it and the people who will actually use it separately. If you put into words the reasons why each person agrees, you will find that convenience alone is not enough. However, the more fun you add, the more you want to check the explanation and quality responsibility as well.