I think the process of posing, setting up displays, photographing, is the adult equivalent of playing.
When I was a child, my imagination wasn't as internalized and refined, it was bubbling over and hectic.
Nowadays, when I look at a figure, set up a pose, a thousand scenarios play out in my head between the characters, the setting, the backdrop of it all.
When I was a child, one scenario was played out while i played with figures, and I had to vocalize it, animate the figures by hand to make it more real in my head.
To me, it's all the same thing, and the only difference is time and mental growth.