In the late 80s and early 90s there was a great deal of blatantly pirated SF, Fantasy, and Anime videotapes for sale at conventions, typically recorded from OTA, satellite, or cable for Western stuff. Anime was typically better quality, copied from Japanese originals with fan dubs added. Some of it was "at cost" where you were paying other fans for the their time, equipment, and the tape. Others were more obviously for-profit, with higher prices and sometimes better quality.

To be clear, this was the only way to get most of the stuff being traded and sold. TV shows or films with no VHS release, or anime with no official dub or American format release.