Surf's Up Bro

Sam and I got up extra early to get to Manly Beach for a surf lesson. It was a lot of fun, and the water was really warm, but it was very cloudy, so once we were out of the water, it was a bit chilly, which made it really hard to lay out on the beach. So we took the ferry back to Sydney. Once in the city, we started seeing these snails all over the place, and we really have no idea what they're for...guesses?