I have had a run in with a goat boater at Mettams once. Decent swell and the R/H was firing with a steep takeoff on the reef and walling up through the middle.
Crowded but fun, chilled vibe then the goat boat came out of nowhere into the line up. I had made the drop over the reef section on a good sized set wave and was swinging up to the lip when bugger me the goat boat fell from the sky right in front of me. I grabbed the nose of the canoe and held him off landing on me as he dropped in.
Gave him a huge spray and the bastard didnt even acknowledge he nearly knocked my head off! It was my last wave so I went in, as I was getting chaged watched him do it to another bloke, unbelievable.
Unfortunatlety for the responsible goat boaters it is the age old case of a minority ruining the reputation of the majority. I have surfed will SUP and goat boaters before and mostly had a good time but you always remember the bad run in's more and they have more of an impact