Hur menar du? Har SUP'are företräde före andra som vill leka med vågor? Varför då? Allmän hänsyn räcker väl?
There are rules to surfing, they are there to avoid injuries and to have some kind of order in the water.Learn these and it will help a lot to keep surfers in a positive mid towards SUP and kayakers surfing.
Surfers will take turns and share waves generally, but if a SUP or Kayak comes along and takes every good wave because they can so much easier, you wont be so popular.
Another point is consider yourself swimming back out through the surf to get into the lineup as a surfer, and a 5m seakayak with some wanna be legend comes flying at you down a 2 metre face, totally out of control (I doubt there is any 5m seakayk in full control in this situation), side surfing and if he or she has any skills to brace upright, this is equivalent of being hit by a bus. It is this scenario that local surfers wont have much tolerance for, and can it create some ugly scenes.
My advice in a busy place, go find a spot that you can catch waves as much as you like, that regular surfers can't. And if you want to mix it with the board riders, wait your turn, and pray you don't hit anyone :-0
Oh and my favourite surf spot when in Sweden, 50meters out from my office, in the playhole in Lissfors, woo hoo! No surfers in sight, and cold beer is just 50m away ;-)