The scope of restrictions in a license don't have to fall only within copyright. Proprietary licenses routinely limit what you can do with or to the software, and don't restrict themselves to derivative works: the license can have "teeth" simply by revoking your copyright license to the original, unmodified software.

If you're thinking, well that still only is effective if your use involves making copies of the software, note that US courts have held that just using software and thereby causing it to be copied into RAM counts as making a copy for the purpose of copyright law (see MAI Systems v. Peak).