I'm not so sure about that. It seems to me that they're selling me a service. Just like I might pay for a subscription to Adobe Photoshop or pay per-render fees to a rendering farm.

I could use Photoshop to reproduce a copyrighted work, and in some circumstances (i.e. personal use) that'd be fine. Or I could use Photoshop to reproduce a copyrighted work and try to sell it for profit, which would clearly not be fine. Nobody is saying that Adobe has to recognize whether or not the pixels I'm editing constitute a copyrighted work or not.