A physical security consultant without extensive networking knowledge puts your physical assets at risk, every bit as much as a network with no physical access control puts your cyber assets at risk.
These are not scare tactics in today's age of technology, they are real business threats. How does your network react if an intruder were to disable an IP camera and use the cable to gain access to the network? How much effort does it take to get into a computer network once physical access has been compromised? These sorts of questions and hundreds more all play a critical role in securing a modern business; both from a cyber perspective and from a physical one.