In copyright infringement cases related to DVDs and such, right holders generally claim their loss equal to the number of copies and on that basis they quote huge figures.
There is an interesting recent (December 2016) court case of the Australian company selling the Burquini (Islamic swim suits) vs a company importing copies pretending to be the branded items. There the court ruled the claim for lost profits unsuccessful on the basis that there was no evidence that any purchaser of an infringing swimsuit would otherwise have purchased the brand product. It was held that merely showing that the company which had sold infringing product of a certain volume did not establish that but for those infringing sales, the rights holder would have sold the same amount of stock.
Isn’t that an interesting precedent? So, acquiring a copy of something does not necessarily imply you otherwise would have purchased an original. The reasons for that may be the price or something else, but nevertheless there is no causality trail there and the court apparently didn’t even want to consider a correlation.
In terms of damages, the issue with DVDs and online media is even more interesting, because the effective cost of production is very close to $0. If fewer bits of clothing get sold, there is a material and production cost there. For a copy of a movie, that is not really the issue. Thus, there is only really cost in terms of the sales process and profit in case of an actual sale.
I am not a lawyer, but I’m putting this out there because I’m interested to see if this judgment will get used in other cases.