Bitcoin was created because the founder satoshi wants to make peer to peer payment system.
He would use bitcoin as the peer to peer currency, so it is not a 'nonsense invention', it is make sense for me.
But i still wonder about the value of btc, why it's value is so expensive.
Bitcoin cannot be a payment system in principle, since a payment is the transfer of SOMETHING from one party to another, and not a process of changing digits. Something cannot appear or disappear by changing digits.