Fees are in most cryptocurrencies. They go the miner that finds that block which includes your transaction. The miner gets a standard block reward (currently 25btc) plus the fees from all transactions included in that block.
The idea is that in the long term as the block reward tends toward 0, the value of bitcoins rise and a tiny fee from each transaction compensates the miners as much or more than the current block reward does which will continue to incentivize them to be honest.
Currently, fees are essentially an anti-spam measure to keep people from creating millions of transactions with the same coin and DDoSing other transactions. I.e. without fees a single person could be issuing more transactions than this stress test did, for free, non-stop.
The idea is that in the long term as the block reward tends toward 0, the value of bitcoins rise and a tiny fee from each transaction compensates the miners as much or more than the current block reward does which will continue to incentivize them to be honest.
Currently, fees are essentially an anti-spam measure to keep people from creating millions of transactions with the same coin and DDoSing other transactions. I.e. without fees a single person could be issuing more transactions than this stress test did, for free, non-stop.