Simple if a well known artist always has beats in rotation the artist can easily get annoyed and skip it. Some actually have signature sounds in their production rather than a vocal tag. I never got why people would use the same rise sound as just blaze used or the sound luger used its like giving someone else credit for your beat. Cardiak uses a flatline sound and most artists probably wont find that sort of thing annoying.
Tagging your beats stops or may prevent some people from using them, and other producers selling your shit like they made it themselves if done right. Major artists jack beats all the time, underground too. Its somewhat like a video and the logo at the bottom right of the screen. People don't care these days, your beats could of been jacked by hundreds of people you don't know about, and probably will never hear about. Its your decision and how you market your stuff. Its tough to decide sometimes to send your beat out to someone and don't know if its going to be used or not when people don't respond to emails. Then you think by not getting a response they're not going to use it, so you push it to somebody else and the first person does use it...now its a mess.
Copyright is the way...still your not always going to be aware of who's on your beat, shit could be way in Europe somewhere.