And what makes you believe that those (basically) peanuts that get bet are the real indicators?

The insiders might as well run a backroom prediction market and just manipulate the public market.

And even with bigger sums: you never know if it isn't just a variant of the shell game. There are no real signals.

It's a fallacy to think all insiders are big players. Small fish want a piece, too, and are not constrained in the same ways the big ones are.