Since we have been frequent visitors to The Magic Kingdom for over forty years we have noticed that quiet areas (or even not so quiet areas) where you could sit down and relaxed have gradually disappeared. After all, someone sitting is not potentially spending money on refreshments, meals, or in the stores. Maybe they are considered to be jaming up the traffic flow if they are not moving along with the crowds.
I'm pretty sure its for traffic flow with MK being so crowded. They added a whole chock full of benches at DHS. If they were against sitting in principle, I don't think they would have done that.