"Steal" has more than one definition. In the context of copyrighted works, it means to distribute without permission, or to make an unauthorized copy of that work.
To be fair, though, given the non-excludable nature of digital goods, it doesn't make a whole lot of sense to make it "stealing" in the first place. Pretty much by definition you can't really prevent access to it. Maybe it makes sense in the context of companies having a hand in the "theft" because they can more readily be made to comply.
When Bobby is accused of stealing Sally's idea for the Halloween costume contest, no one wrings their hands about the non-excludablility of an "idea". Nobody tells Sally, "Bobby didn't steal it, he committed idea-infringement, Sally."
In layman's terms, "steal" is perfectly acceptable. Everyone understands what it means in this context.