I have to admit that the video demonstration with the strobe light is impressive and makes you want to believe in it but: 1) Your only seeing the balls at a fixed speed? 2) That product in the video is completely different, in that their balls are contained in a dedicated ring with dampening fluid? 3) What happens to the loose balls inside your tire when you hit the brakes or accelerate?
How often do you stay at one speed on a motorcycle?
My guess is that you are actually "out of balance" more often than "in balance" while this pile of beads is seeking a good low spot in which to stay.
4) The "goo" products make sense for flat protection, but not balancing. Centrifugal force simply makes an even band of goo all the way around the inside of the tire. It's the same as just making the rubber thicker. I'm also curious if the product couldn't cause you to drive extended periods with an object in your tire that you couldn't detect? Is it really "blow out" protection or just "leak" protection?
I think the belief in this stuff is more a matter of people being sold the idea and trying it with a brand new tire installation. They feel the incredible difference in the new tire ( which happens every time I get new tires without additives ) and then they attribute the great difference to the miracle product instead of the new tire.
I believed in STP "motor honey" for a long time in my teens!