Don't know if I'm too late in chiming in here but here goes anyway..... I currently have 8 albums on commercial release. Officially they are available on Bandcamp, itunes, Amazon, Spotify and most of the other better known streaming sites. That's all well and good and completely under my own control, however on a quick google search I can find my albums for sale as mp3 downloads on many unsavoury websites over which I have no control and from which I receive no royalties. Most of these I have found to be located in Eastern Europe or Russia - none in China so far - and in spite of my efforts I cannot get them to remove my albums from their websites sites, even using threats of legal action. The truth is that regardless of copyright rules or registration as the owner of a given work, there are people out there who couldn't care less and will steal your music to sell for their own benefit and they know that there is literally nothing you can do to stop them. It's a fact of life which every musician has to put up with. I even have some friends who have self released work on Bandcamp as a free download but have still found their work actually for sale on dodgy Russian websites - truth.
My philosophy on this is to simply accept what I cannot change and consider that even if I am not getting the royalties I rightfully should be getting from album sales, at least there are some people out there who are listening to and appreciating my musical efforts. Small consolation in the grand scheme of things but it's all we can really hope for.