The answer to your question is no this is not the norm. I have been spearing for 25 of my 29 years and I can tell you this is not the norm. please dont let a couple of a boatload of idiots convince you that we are all like this. There are a lot of dumb fishos out there who slaughter heaps of fish and be idiots but we (spearos) dont condemn the lot of you.
Just the other day I went for a shore dive and passed a guy fishing I asked him permission if i could swim past him and he was happy to oblige. Its not the form of fishing its the person doing it.
Spearfishing is the most sustainable form of fishing as it is release and catch and very selective unlike fishing where yiou catch wehatevers down there biting.
I am a memeber of several spearfishing forums I will pass this message onto to them and get these guys to pull there heads in.
The majority of us spearos are good guys and we have a strong membership Federation (AUF) which has a stringent set of rules and regulations that all decent spearos afhere to.
Like anything in life common sense prevails and these spearos dont seem to have any but dont label the rest of us.
Cheers Dan