While I understand what you're saying, it's pretty clear what is meant is "$X worth at the price they currently sell for". When there's a story about an object in space made of gold worth 100s of trillians of dollars, nobody believes it would really sell for that much if we captured it and mined all the gold; because the value of gold would plummet based purely on it's existence.

But I agree with you that it would be put into a court document as "it cost us this much" for the full amount, vs the amount they were likely to ever be able to sell (and can't, now that everyone got it for free, so the value is $0)

and yet, most people use this same measure for market capitalization of companies.