In a strict legal sense I think you are right. There is some good rationale for copyright, going all the way back to the 1700s, I think. Most artists pretty much need copyright in order to survive. Also, yes, companies should have the ability to freely negotiate contracts, and to have legal protection against someone breaking those contracts. And, yes, these slogans about piracy not being stealing are legally unsophisticated and facile. That said, you can probably sense the "however" coming...

HOWEVER, the context is important. All law is based on an implied social context. When companies engage in practices that poison the market, they break the implied social contract underlying the laws that protect them. The result is retaliatory behavior by consumers. It doesn't matter whether we're talking about media and games or food prices. People will steal when they feel the law, as applied in a particular social context, is no longer fair. It isn't morally right, but it isn't exactly wrong either. It's more of an inherent market mechanism to curtail shitty corporate behaviour, and that's why governments tend not to interfere too much with individual downloading.

When there is no easy way for consumers to fight back, that's when governments need to get involved. Ridiculously high drug prices being a good example.