[Right_Wing_Madman]

Transactions are processed by miners aren't they...hence the transaction fee paid to miners? And the system is maintained by miners, isn't it?

You got it. The Bitcoin transaction fee is about $4 right now.

[RoosterRedux]

My confusion is that the bitcoin systems seems to depend on an "ethos" that would prevent a group of miners (even a company) from damaging or undermining the system because their revenues would decline.

But that dependence on an ethos overlooks the fact that some humans don't give a damn about an "ethos" or the system and would be willing to destroy the system for profit.