I've been spending a lot of time with some of my friends and family's kids lately. All boys aged 2-6. I know, and yes I'm still as sane as I was before... which might not be saying much. Lol.
One thing I've come to notice is how randomly creative that kids in their age range are. A lot of the time a kids first 'real' toy will be some kind of action figure or doll from a favorite TV show or movie. What I find interesting is that no one teaches a kid to play with one of those things, but what do they do? Pick it up and make it talk. If I wasn't already used to them I would be surprised at the amount of detail the kids put into playtime. I'm fairly certain that if I listen close enough that I would be able to get a plot for a new story out of them.
The younger ones tend to go for the action. ("I kick you. Jump over here!" "Oh no, I crash!") The one in the middle could hold a conversation with two of his guys for who knows how long. The oldest, however, likes to play with words themselves now. He likes to make up words and exchange random words with the word 'fart' a lot... I don't know what any of it means but as long as he's having fun I guess!
I do remember playing with action figures and dolls when I was little, especially at bath time, and to be honest I miss it! Being in the frame of mind where nothing has to make sense and having whatever comes to mind fall out and essentially come to life through the toys was fun. But kids grow out of it, as they will do, hopefully moving on to equally creative games and interests. And adults grow out of it even more.
But some of us grow up to keep playing. I do. I just exchanged my dolls in the bathtub for pens on the paper.