It's very frustrating to say the least. There are too many people out there that have absolutely no respect for anything or anyone and are truly ignorant to what is acceptable in our society. And no this comment isn't directed to any ethnic group, just individuals behaviour. It's good to see that they are cracking down in this instance but the chances of getting caught and the fines so small that it's not much of a deterrent.
Unfortunately there are far, too few CO's out there to effectively conduct random patrols with any regularity. It's up to all of us to report abuse of our resources whenever we witness it, and to call people out for this type of behaviour; or any other anti-social behaviour for that matter. You don't have to be aggressive or threatening, just let them know that others are watching and that what they are doing is wrong. Depending on their reaction will dictate whether you educate over a friendly chat, or walk away and call the authorities.