You might be over thinking it a bit mate.... I been boat camping at Moreton for many years....not had an issue yet but yes it could happen (Most likely some dipshit loser - there are plenty about)
* I have a good anchor and more importantly 15M very good quality chain and braided anchor line - let the boat swing around the main anchor, having rear anchor is asking for trouble (Think swamped boat!). I wrap a towel around the rope to protect it from chafing
* I make it look like someone on the boat as best I can, I choose a spot to sleep where I can watch the boat, doesn't make for a good nights sleep but if I hear a boat I wake up and watch what they doing, unlikely some grub will swim out at night from shore so its boat based dipshits you need to keep an eye on!
* Anchor deep enough to make sure doesn't bang on the sand at the bottom of the tide
* In the unlikely event something does go wrong - that's what insurance is for so relax and enjoy the experience!
My old boat, new boat has a cabin so normally sleep on the boat these days unless bumpy conditions.
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