But does it make sense? I'm not sure it does. I'm not going off of well formed child development theories, just my own common sense, but really to me it doesn't make sense to essentially bastardize every toy that sells well by spinning it into a multi-movie "brand", nor does it make sense to me to have a movie and then do the same to every aspect of that movie, just to sell what amounts to more plasticated crap taking up space in the home and on the planet. As James illustrated with his clothespin laser gun, he probably had way more fun with that, than a plastic version that will break after a few uses.
Getting to your last sentence about how much a toy's brand and the child's perception of that brand can limit the quality of creative play, I'd say probably it limits creative play quite a bit because there are already well established stories, roles, and outcomes that the child has already experienced through the movie or game versions, so it would make sense that a child would be more likely to recreate those scenarios over and over, maybe with some variations, but essentially copying what s/he has seen in the movie and games. However, if you give a child a box and some clothespins and whatever else you have laying around, their starting point is, to me, purer imagination because they first have to do an inventory of what bits and pieces they have, then consider what they want to create, then create that thing, then create a story in which to play with the thing they created...I don't know if I'm making sense, and I'm not a parent so I'm not speaking from an experienced parental/observational perspective, just a common sense perspective based on my own life and what I've seen others do.
[On a scale of 1-10, please feel free to rate my thoughts - based not on concrete data or experience - as: utter BS, semi-cohesive, complete crazy babble, wow you should work for MIT...Go ahead, I can take it...;)]