Optimization isn't efficient on the grand scale of things. Think of these robots more as exchangeable worker units. Lets say the warehouse isn't accepting many packages that day. So you don't need as many robots at the loading dock. But we have a lot of product that needs to be inventoried or shelved. Send a couple over and have them start doing it right away.

You actually end up running a warehouse with less robots because they can easily be repurposed for other duties.