To people who want to get paid for their digital works, myself included, that is a bit of a problem. All of society and economics is based on an old outdated model where giving something to someone would rid the original owner of their copy, so everyone who wanted a copy had to buy one from someone else who would lose theirs, and the only source of new copies was you. There might be actual development costs involved in making these copies. For example, for every wheel in the market, someone had to make that wheel. With digital copies, you only need to make the wheel once...
If someone pirates Minecraft instead of buying it, it means I’ve lost some “potential" revenue. Not actual revenue, as I can never go into debt by people pirating the game too much, but I might’ve made even more if that person had bought the game instead. But what if that person likes that game, talks about it to his or her friends, and then I manage to convince three of them to buy the game? I’d make three actual sales instead of blocking out the potentially missed sale of the original person which never cost me any money in the first case.
I won’t bother analyzing why people copy games and other digital media, as that’s really a moot point. We’ve got an amazingly effective way of distributing culture that is extremely beneficial for humanity, but it clashes with our current economical models. Piracy will win in the long run. It has to. The alternative is too scary.