DISCLAIMER: This could very well be all bogus, I'm talking about my intuition as a beginner/intermediate economics student, you have been warned.
I got the feeling agents do not just maximize utility but minimize disutility as well. Now my understanding is that from the convexity assumption follows that those problems would have the same optimum. But I think it could very well be the case that the utility function does not at all look like the disutility function (also different variables) and optimum of those two functions need not be unique (Am I with the duality gap on the right track?).
If this at all a valid intuition I would appreciate some pointers to empirical studies that examines utility and disutiliy, or some theories that incorporate the notion of disutiliy (not just as an inverse of utility) into preferences.
P.S. I got the idea while reading about The Paradox of Choice from Barry Schwartz (more choices could lead to confusion and in my interpretation disutiliy)