I believe its because the type of metal is a valuable one which makes it much more valuable than its face value
Er, no. It was made out of brass by a car wash token company.
The value comes from the rarity, though it actually isn't that rare compared to other ones. It was the first though and many will have been abused as they were worth about $20-30 when new.
It is also the physical representation of Bitcoin that everyone knows, I think there are special gold and silver minted ones as well.