The average transaction cost is around $40 right now. You have to consider that each block mines coins, and the miners are getting those at the cost of everyone else. A decentralized system will be more expensive than a centralized one. An bitcoin transaction fee is going to be about 40 cents, plus $40 per transaction for the block reward. The value of bitcoin is that you can trade resources for trust. With traditional money you have to trust that visa or your bank will not just zero out your account.