Snorkling

So I'm talking with a friend about a trip to Australia that I'm planning, which will include a stop in the Great Barrier Reef city of Cairns. The conversation turns to snorkeling.

F: "Have you ever gone snorkling?"
BRD: "No. Well..."
F: "What?"
BRD: "Well, when I was ten, I once went swimming in Lake Michigan with a snorkel."
(pause)
BRD: "That's not the same thing, is it."
F: "No."