I had exactly the same feeling, but some of my Japanese friends explained to me, that it's just Japanese "style". I don't thing it's Japanese style, but maybe it's Tokyo's style, especially at the big events. One thing I cannot forget happened at the Astrix / Pixel concert. I wanted to go to the bathroom and I couldn't believe the length of the line of people waiting there. I thought WTF?!, so I just went ahead to see what was happening there. When I got to the toilets I realised, that the guys weren't standing in line for the toilets, but for the mirrors! No kidding, the guys were brushing themselves up and doing their hair! I mean...WTF?! There was so much hairspray in the air that it would have probably caused an explosion if someone would have lit a cigarette. And I found that that was probably the reason for the people not to dance:
The (often very, very beautiful and stylishly dressed) women could not dance because of their high heels. I never saw women wearing high heels at a Psytrance party anywhere else.
The guys could not dance because if they would have, their fancy hair constructions would have collapsed. It was all about style, not the music, at least that was my impression.
Of course I don't want to generalize on that, because there have been other parties as well. I think it has become pretty obvious that the bigger and more popular acts become, the more the crowd diversifies. That's why it's called Pop-Full-On...or Pop-Progressive One will just find "regular" party people, who don't really care about the music, as long as it's danceable. Then there are lots of people, who are only interested in drugs, of course. For me it has become difficult to tell, if a party will be a good party, or not.