We had an example over the bank holiday when some poor soul passed away and it was a while before his body was found. The emergency services attended and were able to gain access easily as the barrier was up. Had it not been, they do have the code, unlike the vandals who recently ripped it off and stole the traffic lights off the bridge. No doubt they will be looking at the circumstances surrounding this death and as to why he was living on his boat in the marina.
Unless you have a properly, registered residential berth I wouldn't admit that you live on your boat. You may spend alot of time on it. As we don't live on, we do want security for our boat when we are not there. We must have chosen the wrong spot. We regularly witness the public coming in and using the place like a park - having picnics and even lighting barbecues. Their children and dogs running amok, often walking down the jetties to look at and play on the boats.
We do have to admit that it is in a beautiful position and it may suit some people; but having lived on ourselves for 15 years until recently 'going on the bank' and having over 30 years of boating experiences, we feel it would be naive to think nothing would ever happen. Unless secuity improves we won't be renewing and will choose a more secure mooring.