He moved to a semi private area (probably not knowing he was being filmed) and let some heat go from his head. I've seen much more impressive tantys in the middle of a shop over chocolate bar.
they might be role models to some, but they're also "at work" when they surf. There is a great amount of pressure on them to perform (get results). It's hardly surprising that they lose their cool on occasion when things don't go well.
From the footage it appears that he walked off the beach quietly and did his best to be somewhere private when he lost his cool. There are far more public televised displays of supposed role models losing their cool at a fellow player often enough through each winter in australia.
That poor board though....