Have you ever see a dog that seems to "pretend"?

Occasionally I will play a game with my dog. I take a few kibbles of food in my hand and toss them to her one by one. She then catches the kibble, jumping or chasing it if necessary. She really seems to enjoy this.
Sometimes it seems she wants to play, but I am busy doing something else. She will take a kibble out of her food bowl, and run with it off to another part of the house (similar to her behavior when she’s given a treat) almost as if to say, “I can’t get anyone to play with me, so I’ll pretend they are”.

Something else she does that seems like pretending is this; she has several stuffed-animal type toys that she seems to treat like puppies. She will take one of these toys, lay down on her bed, and “groom” the toy with her tongue while holding it between her legs. (She was fixed before we brought her home about 9 years ago).

Is this pretending, or is it some other instinctive behavior?