Not really. Even they will carve out some niche and pretend (even to themselves) to be doing useful work. Middle managers love to schedule irrelevant meetings, but they will provide some business justification to themselves and to others. You'll find the odd developer that's maintaining some internal app by themselves.

It's very rare that employees are just twiddling their thumbs and doing nothing all day. Specially if we are talking about a highly skilled workforce. I've seen that more often on boring entry level jobs - because the jobs are already boring by nature, so doing nothing and doing something is not much of a difference anyway.