Ah...the games of darts. Great fun. The Earth people throw these at a board and the best thrower has glass containers of warm brown liquid bought for him.
After many of these glasses the thrower sings and finally falls over...an interesting custom.

Good theory, but you're way off. This is another example of a coin. This one's from West Africa from about 150 years ago. The advantage of these is that they are made of iron. Earth people from West Africa could melt them down and use them for something else if the need arose.