Not every town in the world has its own natural ice maker. Pieces of ice break off the glacier and eventually float to shore. Locals are in the habit of going out and getting the ice to fill their ice chests before they go fishing. I remember on several occasions as a kid going out to get ice to cool our homemade ice cream. Dad would put waders on and chip away at a small berg with an ice-pick. We would then crush the ice and add salt. I am not sure the ice changes the flavor of the ice cream but I don't remember any that has tasted as good since.