And what if it is just what is just as it says. A way to save energy.
Optimizing the workspace is not a bad thing. Done right, it is win/win : more comfort for the employee, more productivity for the company.
You are probably thinking about the boss monitoring every movement of his employees in order to punish them later if they take too many breaks. Truth is : the boss doesn't give a shit. In fact, the ideal employee is one you assign a task and forget about him until he gets back to you with the work done.
As an example, I know sysadmins who know exactly what people do on the internet. They know some people spend hours on the internet not working. Their boss know it too, they don't care as long as the work is done and that this activity doesn't endanger the network in some way.
In my own work, I happily go on non-work related sites all the time, with my own session. And yes, they are watching, and I never had any problem. Only once I visited a site that was considered a security threat and they got back at me asking me if I did it willingly, I said yes, explained why, and it stayed there. It wasn't a very good reason but at least, they knew it wasn't malware or an intrusion and it is all they needed to know.