I don't really post a lot of work on the internet, but I still have yet to put a tag on since like 04, six years ago.
Tags are just annoying, imo, and I also don't just hand people a track unless we've worked details. Half the time I don't charge for beats, sometimes I do, all depends on the project, skills and budget.
Also, I trade a lot, seems to work better, but you just have to make sure you get your trade up front or at the same time they get the beat.
I've been jacked a few times that I know of, and I'm sure many more I don't. Big deal. I call it flattery, but biting is the biggest form of it. Someone jacks your track, just make sure you have it copyright-en.
Also, it comes down to personal pref. Even having a track online with no download, someone can use the internal mixer on the soundcard to just record what they're listening to. Sure quality is a factor, but most broke cats aren't going to care that they quality is low, they just want the beat to rap on.
I don't see the point to a tag, and I've turned off more instrumentals due to over tagging.