Without sounding too sanctimonious, what is happening is theft and vandalism on a huge scale, and the behaviour of those people on the beach is actually disgraceful.
I do hope that the perpetrators get prosecuted.
What would the feeling be if there was a car crash, and the same parasites started rooting through the boot and helping themselves? They pretend it's a 'victimless crime' by assuming that insurance will pay for it all, but I'm afraid that's a poor excuse for behaving like vultures.