I reached the other manufacturer of cam cleats and she was all
surprised, said that theirs are used all the time for hanging fenders.

Anyway, the key benefit of the cam cleat for this is you hang the
fender "too low" for the pier you're approaching, then zip it up to the
correct hieght when you get there before the boat touches the pier.
Sure you can pause in the water while you get them right on a
conventional horn cleat, but when you have a boatful of landlubbers
like I always do, with wind, it's not always practical.

MVG