Quoted from SuperPinball:
Ever since China entered the World trade organization, the U.S has closed 5000 factories per year. They thought back then that the Chinese were incapable of manufacturing quality goods at cheap prices. Today everything from the underwear and t-shirt you wear to computer electronics is manufactured in China. The Chinese manufacturing capability currently surpasses the U.S. To take a pinball machine like Medieval Madness, strip it down, and make exact duplicates is not far fetched. They easily have the capability to do so and at a price point sub $1000. The more labour intensive something is, the greater their advantage. Planetary Pinball could have easily contacted one of these companies instead of C.G. or Stern to take a Williams Pinball machine, copy it and re-release. I think we will see exact copies of the most popular pins coming from China in the near future. Pinball is not exempt from the same economic forces that drove any other manufactured good to China.
I seriously doubt you will start seeing knock-off pins anytime soon. There simply is no market for it. I know it happened in the 80s with High Speed, but the pinball/arcade market was an entirely different beast then than what it is now.