I actually got to confront some of the white van guys back in the early 90's. They parked an all-white truck (about the size of a midsize U-Haul) in the parking lot in front of my retail store (which was known as The Speaker Shop). A customer came in and told me there were guys selling speakers in my parking lot. Acoustic Monitors. I went out and told them to get the heck out of there or I would call the police. I got a BS reply that they were doing business just like I was, competition is what business is about, and this is a free country so go ahead and call the police. My response was, they were conducting business on private property that they didn't own or weren't renting, and they were conducting retail sales without local and state sales tax licenses. They weren't happy when they left, but it only took about a minute after I walked back into my store for them to leave.
True rip-off artists. I had a number of folks bring their WV speakers into my store to fix or replace blown drivers. As soon as I saw what the speakers were, I could quote almost verbatim the sales pitch used by the sellers when the poor souls bought them. The line they were using here was, they had just completed a nightclub installation of a new sound system, and they over-ordered speakers for the job. You could get a pair of speakers for $400 that were worth $800 each. I'd say the average price paid by the uninformed buyers was about $250/pair. None that I talked to paid less than $200.