If I recall correctly there are more fishermen than golfers and tennis players combined. Of course, tennis players do not attempt to play in rain. This certainly contributes to the reason there are more fisherman victims.
According to an electrical engineering professor who gave a presentation on lightning, golf courses are especially susceptible to lightning strikes because of the electrical potential that exist resulting from being well fertilized and well irrigated. I would think subdivision lakes would be more susceptible than clear mountain lakes because of runoff from lawns containing fertilizer, etc.
I have been caught on lakes in my float tubes because I could not get off the lake in the time from the point when I determined I was hearing thunder until the storm was over me. I remind people frequently the fastest you can move in a float tube is really slow.
"Patriotism supporting your country all of the time and and your government when it deserves it"- Mark Twain