I use the #paid-media since people thought there was a need for it when it was introduced. I don’t have a strong opinion about it. I’ve also started to request not sharing direct download links like Mega since I mainly script VR and we don’t want to endorse outright piracy by sharing videos. VR is still a niche product compared to mainstream 2D.
My interpretation of the #paid-media tag is that the video is from a commercial site and not something someone put together (PMV, CH, animation or shorter clips from full length videos) and shared on sites like PH or Spankbang. The tag serves as a help for users in filtering content since this forum engine is focused on tags rather than dividing it into sections like the older RTS site (although we have gotten more and more categories since tags are more difficult to manage, which this discussion shows).