Just got back. Chartered with The Moorings and they advised us to lock the dink to the boat at night (monohull with no davit) and to any docks. I'd say the majority of dinks I saw were locked to the various dinghy docks and I locked most places except for short stays and places like Willy T where people are moving dinghies all the time to get in and out. The Moorings supplied a long cable that looped through the motor and then back to the dock/boat.
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