He also booked Browne for 'kicking the ball away' (really just back to where the free kick ought to be taken) and then did absolutely nothing when a Portsmouth player did the same a few minutes later. I would have thought it was easier for the ref without a crowd (less pressure, easier to hear etc). Not sure it worked out that way though.
Tbf, on Browne's booking he was right. Browne kicked the ball 3 times to the wrong place then he pushed his luck and kicked it again so got booked.