I've noticed and tell me if you guys agree, it is usually on fresh water where I hear most stories like this. I have heard a lot of them from the divers in Michigan, I think especially on inland lakes people are not accustomed to Diving, they think of it as a purely "Ocean" sport. I even had one guy ask me "why would you want to dive an inland lake, there are no reefs or sharks" I said well you just answered part of it, there are no reefs or sharks! A change of scenery is nice, not to mention if you happen to be one of the lucky divers in the Great Lakes to find a load of 150 year old Virgin White Pine timber and sell it for millions like the guy in Minnesota did up in Lake Superior. I will have to find a picture I have around here it is pretty hilarious, I was out Ice Fishing on Lake Margrethe in Northern Michigan when I saw a Diver Down flag sitting on the ice with three guys by it, I was not a diver yet but thought it was hilarious to see fishing shanty's, people in down parkas and hunters orange suits sitting around fishing and not 100 yards away there was a diver down. Turns out about a week before a drunk on a sled (snowmobile) had gone through the ice, he lived but they had to find the sled and bring it up.