In all likelihood, those people are under pressure from their bosses. They need the appearance of everyone being there and working hard. For some people in managerial positions, any kind of data showing the employees still working won't be enough... They want to see asses in seats and all at the same time.

I've had to work under many executives like this and it's pretty annoying. They can't be reasoned with.

Oh and the faster your people work - the worse it is for people who rely on headcount for their job. They can't justify a larger headcount if everyone is working efficiently...