History – What are the transaction fees incurred by Bitcoin users since Bitcoin was launched?

Because Bitcoin has no identity, it is impossible to know the total fees paid by “users” of the system. For all we know, the miner may have included a transaction that pays a fee to itself.

Actively monitoring transactions that are mined after being broadcast to the P2P network can yield fairly reliable estimates. The fees charged for transactions can be collected by any miner, so it is assumed that such transactions are performed by users.