However bills cost 4.9 cents/dollar for $1 bills and half a cent per dollar for $20 bills. So the vast majority of money is much, much cheaper than a bitcoin.
[1]: https://www.usmint.gov/wordpress/wp-content/uploads/2016/06/...
Coins and cash actually get consumed as they degrade and/or get lost or destroyed. You need to replenish the supply.
But you can circulate bitcoin forever.
You need to compare transactions.
How do I send you cash? You can give me an address to meet you at. We both drive our cars or take public transit there and consume some amount of energy and time to meet up. Then I give you cash.
Or you could just tell me a bitcoin address to send to.
You have to compare Bitcoin to the concept of money, like U.S. dollars, but not literally the paper. A comparison to bars of gold is OK however since that is money and not a representation.
Bars of gold certainly are a "representation" of money. They are only worth something so long as we all say they are. (Besides the little bit of intrinsic value from electrical wiring.) If people stopped saying gold was worth anything, it wouldn't be.
Btw, you can buy pizza with gold, I guarantee someone will take your gold for pizza.