WorkinHard, it is not a CAT versus GAT thing.
Any CAT-pilot will immediately aknowledge the fact that there is too much 'chatter' on 121.5, be it inadvertantly (fingertrouble when manipulating multiple radios on a multiple sector day) or otherwhise.
So, I do not persist in blaming GA only. Read my disclaimer. I fully recognise that practise PANS are legitimate use of 121.5, I fully recognise that CAT plays a substantial part in chatter, but is it, in your turn, so hard to admit that on certain sunny days these practise PANS also add a fair deal to the chatter?