I use to work in retail as a student and this was generally a requirement of banks or credit card companies as an insurance and not so much the retailer so that in the event there had been fraud committed you could show you at least took the minimum steps required to allow the transaction to go through, then the bank or CC company would take the hit.
If you couldn't prove caution was taken, they'd reverse the charge and the retailer would take the hit.
For us, camera footage of us "verifying" signatures or ID was enough.. heck even if they didn't match.. as long as we showed us double checking it was insurance enough for us to keep the money.
It does sound like the warehouse needs to pickup its game though, that type of verification method is out dated by about 10 years.