I agree. Here's another example for your arsenal. A friend of mine was doing "conservation" tests for a Piaget-inspired study some years ago. This is the one where you pour blue liquid from a cup into a tall skinny tube. Then you pour the liquid back into the cup. Then you pour the blue liquid into a short fat tube. Then you ask the kid who is watching all this which tube has more liquid: the tall thin one or the short fat one. Most kids, Piaget argued, will argue that the tall thin tube has more liquid....up to a certain age, then after that age, most kids will realize that it's the same amount of liquid. OK. So he's doing the experiment and all the kids are younger than the age at which they understand about conservation and they're all saying that the tall thin tube has more liquid. So my friend gets bored and he goes to the soda machine and he gets some orange crush, which he drinks with visible delight. Then he decides to see what happens if he uses the orange crush rather than the blue liquid. And guess what, now all the kids can conserve!!! Moral of the story: sometimes a subjective interest in what is going on can make you more intelligent. The kids didn't give squat about the blue liquid; but they cared very much what wasa happening to the yummy soda.
Joanna