http://www.businessinsider.com/alex-stamos-leaves-yahoo-to-b...
As does Google: http://www.csoonline.com/article/2928798/security-leadership...
As does Twitter: https://www.linkedin.com/in/mcoates
as does Uber: https://newsroom.uber.com/joe-sullivan-joining-uber-as-first...
As does Apple: http://www.reuters.com/article/apple-encryption-executive-id...
As does Amazon: https://www.rsaconference.com/speakers/stephen_schmidt
So I would say its pretty common. Just because its not common at the Ashley Madisons and Targets doesn't mean its uncommon elsewhere.
