Your reasoning would suggest that the owner of the media should be able to predict their future capital and be able to sue based on that? What if the media sucks and 10 people bought it and via word of mouth told others not too and then you have some that will stumble on it via torrent sites, try it, then delete it... Speculative markets are bad imo
You make a very valid point, Gary.
But with market research and even minor demographic surveys you can at least get a feel for how your product is perceived, even though that may not directly relate to sales numbers.
When a new product is bound for the market, those kinds of numbers are all you have to try and estimate what you need to do to make it happen.
Releasing a demo can be an invaluable tool, but is not always an accurate gage of what will happen. Creating a demo means you walk a fine line between giving too much (demo is good don't need full version) and not enough (demo is too crippled not going to buy).
There is no simple solution and I honestly think that many of the game devs and publishers are trying just about anything they can think of. You will notice that a lot of the MMOs are going to a "Freemium" model. This is easiest described as an MMO demo. The players who become real fans will stay and buy into the game (through whatever revenue stream you are trying to generate).
You also see the "Idie Bundles". This does not make an indie developer diddly, but it gets their game and name out. This is a crap shoot for them in terms of any viable revenue.
In my opinion, what game companies need to do is a "shifting revenue" model. There is no reason that a company has to stick with a single method of generating income over the life of a product. You see this a lot in the movie industry (Theater release -> DVD -> Netflix -> general OTA viewing). As one model starts to decline, create a new one and keep your product as relevant as you can, for as long as you can.
Okay this really diverged from DRM to market analysis, but oh well. lol
As always, just my opinion.