Me neither, but I learned that :

• kids really like it, you can bubble and stuff,

• it is useful when you drink from a can cause the border can be soiled (by rat piss or other tasty stuff, by the way if you drink from a can you should always wipe it with a cloth or clean with water before putting your mouth on it),

• a guy I know who can't use his hands, so his only way to drink without help is with a straw