Note also that this could be due to the fact that clicks (and I suspect likes as well) that come from the internal company networks (which includes VPN) are not

Note also that this could be due to the fact that clicks (and I suspect likes as well) that come from the internal company networks (which includes VPN) are not billed to the customer, and are not counted for anything involving revenue. Google/FB employees spend much of their time at work or connected to work.