> You can't profit from other people's copyrighted material without their permission. That's just how copyright works.
Sure you can. "Fair use" is the most common example of that, but you don't need to make a fair use defense in order to find examples of people profiting off of others' copyrighted works legitimately.
In fact, it should be noted that a lot of famous songs you probably know are themselves based on copyrighted works. Coolio's "Gansta's Paradise"[0] and Kanye West's "Stronger"[1] are very famous examples. Not all samples are licensed - it's very common to use unlicensed samples, even in music released by major studios.
I don't know which artists are with which labels off the top of my head, but I'd bet anything Universal is profiting off of unlicensed samples for some of their artists. Many (most?) Soundcloud users, on the other hand, aren't making a single cent off of the music they post.
[0] samples large parts of "Pastime Paradise" by Stevie Wonder
[1] samples Daft Punk, but this was actually itself sampled Edwin Birdsong's "Cola Bottle Baby"