Yes, we all know that "great artists steal." And of course, every musician has been inspired by some one before. There are only so many chords. But that's a red herring.
When musicians directly copy another's work, i.e., sampling, don't they need to get permission? And if the owner of sampled work says "no, you can't have it", then that's that.
Again, easy to do =! ethical.
Mass surveillance has become widespread. Deal with it.