You may be right that the music companies are not acting in their best interests by aggressively attempting to shut down copying. I've seen some articles contending that certain copying encourages music sales by allowing consumers to sample music they might not otherwise hear. On the other hand, digital copying is a lot easier (and less time-consuming) than taping was, and there is also the general consumer perception that digital copying results in a "perfect" copy (bits is bits) that taping never did, and companies are understandably concerned that digital copying may represent a threat that analog taping never did.

Whoever is correct in the debate, however, the issue whether the companies are acting wisely and in their own best interest is different from whether they have the right to prevent copying.

Unfortunately, we are at a point in the technology at which preventing or limiting copying is feasible, but only if executed in a clumsy and intrusive way.

One way to limit the confrontation may be to have more "artist" (God, I hate that word) input. As you suggest, the Rolling Stones may want copy protection on their discs; everyone knows who they are and sampling is unlikely to increase sales. An obscure band issuing its first "major" label album, on the other hand, might want to encourage sampling and copying in the hope that it will generate greater exposure and ultimately sales.