Customs agent taking passengers photo on outbound flight to Canada...

I just had my picture taken by someone claiming to be a customs agent on what appeared to be a phone. He was taking all passengers pictures. This was right before boarding the plane after they scanned you into the flight. He said it was so they could match your face to your passport on re-entry. Is this a thing? First time I've encountered this and I travel to Canada frequently.

agent canada flight privacy