When you run into a store and steal a copy of Adobe Photoshop, Adobe hasn't lost anything because they've already been paid for that copy. It's the store that loses money, because they paid money for the missing copy and now must pay more money to replace it. When you illegally download Adobe Photoshop, Adobe still hasn't lost anything unless you would have been willing and able to pay the $700 for it if not for the ability to download it instead. The only thing they are "losing" is a sale; that is not the same thing, morally or economically, as theft.
Let's say that every year, a company produces 100,000 loaves of bread; they sell 90,000 loaves and 10,000 loaves are stolen. Those 10,000 loaves of bread are a real loss to them; it cost the company a significant portion of the loaves' sale price to bake them, so every loaf stolen represents the loss of that amount of money not counting the profit they could have made if they'd sold it. If they could control theft and have no loaves stolen, in exchange for only producing and selling 80,000 loaves of bread, this is a gain for them. They make more money despite selling fewer units because they have fewer losses.
By contract, let's say that a different company sells 90,000 legitimate copies of a piece of software and 1,000,000 copies are illegally downloaded. Those 1,000,000 illegal copies didn't cost the company a dime. The company didn't even produce them-- if they're on any kind of physical medium at all, the software pirate had to provide it himself. The company only has a hypothetical loss, of however many copies it thinks it could have sold if people weren't capable of downloading them; if they think even one percent of those downloads are real lost sales, they're spending far too much of their meager salaries on drugs. If the company could implement magical DRM that means that the software can not be illegally copied, at the expense of only selling 80,000 legitimate copies, they're losing money. This is what IP creators and distributors need to learn; if you can make 10,000 additional sales at the expense of allowing 10,000 additional illegal downloads, that's more money for you. If you can make 1,000 additional sales for 100,000 illegal downloads, that's still more money for you.
There is no "shrink" in intellectual property. Sales are the only number that matter and the only number anyone should pay attention to; anything that increases sales is good for business, no matter how much it also increases piracy, and anything that decreases sales is bad for business, no matter how much it decreases piracy. You don't see a dime from secondhand sales of your IP, and the overwhelming majority of used book purchases are lost sales; it's funny that you never see anyone comparing that to theft.