[RealJames]

That's a very common take on it dogsbody.
I think that westerners coming to Japan often feel very very frustrated by it due to perceiving it the way you do, as I did actually.

I've come to see it differently now, perhaps not the way Japanese people see it, but it helps me go along with it.

In the movie example.

If some friends want to go, and others don't, and they all go, then some will feel a little apprehensive about it but they'll still all enjoy each others company as a group.
If they don't go, those who'd wanted to go would be apprehensive about not having been able to go, but still would enjoy each others company as a group.
If they split up and each do as each one pleases, there's no longer a group.
The individuality forces each person into isolation.

Say now we introduce the all-powerful democratic force. The majority rules and they don't go to the movie, then the minority may be apprehensive but they still enjoy each others company as a group.
Except, it keeps happening, the minority keeps getting voted out and eventually segregates or isolates from the group once again.

This is just how I've come to see the importance of harmony in Japan, I'm not pretending to be voicing the opinions of how Japanese people feel about it.