Having just discovered this thread, heres my opinion for what its worth.
I've fished the pier at Cromer regularly in recent months, and the vast majority of locals who fish it are decent guys, not the brainless unemployed clods described on here. However, any pier will inevitably collect a few pillocks.
A lot of the large bass are kept, however I have also seen decent fish returned. Many of the regular anglers ensure that undersized fish are returned, when caught by idiots who want to disregard the minimum size limit. And there are a lot of these idiots.
I'm not sure if its correct to think of these bass as "resident" fish, they come and go according to the weather and mackerel shoals. This year during June, July and August there were long periods where there were no bass at all. Also, each shoal can contain its own individual strain of bass, distinct from other shoals. For example, a shoal of very short, stubby fish might appear one week, and different fish another week. This suggests the bass are visitors rather than residents. It's not the same fish going round and round under the pier all day every day.
Of course, killing these fish will still damage the stock, especially if female fish are kept. The big ones must be approaching 20 years old.
Apparently 99% of the bass have been caught on live mackerel, and dead baits have been rejected. Surely this will limit catches because the opportunity to get hold of livebait here is limited.
Personally, I think there is nothing wrong with taking fish, within reason. But photos of rows of dead bass lined up along the pier don't do anglers any favours, lets be honest. Its easy to understand peoples rage when they hear about the slaughter of large numbers of these fish. The fish may get wiped out, or they may not. If they do, those responsible will have to live with it.
This year I have been lucky enough to catch 83 bass from the pier, mostly smallish fish on feathers, but with a good few large fish including one into double figures. Out of these I have kept 6. Is this wrong?
And yes, the bigger ones were caught using 60lb line and 6/0 hooks, under the pier, and I d@mn well enjoyed it - even though I prefer conventional fishing methods, fishing a beach in winter. Different species, different tactics. Freshwater match fishermen probably think 15lb line and 1/0 hooks are over the top, and they may be right.
Just a few thoughts, make of them what you will.