In reply to Gary Gibson:
Can I add to what Gary requests and ask climbers to consider 'having a quiet word' about best practice if they see any climbers doing this. I suspect most who do this are not even aware they are doing anything wrong, and very few will read UKC forums as avidly as they would need to to receive this message. We need action as a community if we don't want to see sport belays being needlessly trashed.
Incidentally, Gary is retiring soon, so other volunteers will have to pick up the work involved in replacing damaged belays. Given the huge amounts of work he did every year he will be sorely missed.