[benologist]

Relying on physical vs ephemeral conveniently ignores that the cost to reproduce something has no relation to the cost to produce something. The other person/party not being aware of what you've done is pretty irrelevant regardless of whether something is physical.

In the real world you also have criminal law between you and the other person before you purchase something and establish that civil contract.

[bediger]

The bulk of economics is against you. In a competitive market, prices fall to the marginal cost of production. That's almost axiomatic. One only has to look to fashion markets, where the leading players have almost zero monopoly power and to PC hardware markets.

What you're implicitly advocating is setting prices without regard to market forces, without regard to the value that consumers place on a good, without regard to increasing efficiency of production via price competition. At best this is short sighted, at worst it kills entire markets.