ahem
im going to go out on a limb and guess, or assume, or suggest, in response to what sems to be what everyone has trouble understanding, is that the 'happiness' that the greyed out characters seem to have is mindless and false, and pales in comparison to the happiness that is possible for people whose souls have not become inhibited and 'redirected' by society's expectations.
in other words, the only reason that they are happy is because they are stupidly obeying and find a kind of bliss-in-ignorance where, because they follow "the system", are rewarded accordingly whether or not they are true to themselves. or at least true to what their selves were, at one point, before their individuals were devalued.
society is set up so that people can 'succeed' without thinking or feeling. if all people want is to go to school (or not), get a 'good job', get married, buy a house with a white picket fence, and have kids to complete and restart the cycle, then that path is laid out like a board game, as the whole of society is eager to accept more cogs in its machine.
to go against this is what is truely challenging.
I give a 9 because the animation wasnt the BEST, though still ambitious, but the concept was one that i've always noticed rearing its head in a lot of real life situations.