I don't know anyone who bets on politics, but I've heard it's pretty tightly regulated (even beyond how tightly regulated sports betting is). I believe there are limits to how much one person can earn from it. If that's correct, it makes sense that inefficiencies could persist.

I'm sure we have similar views on conspiracy theories. I also doubt the elaborate ones, but I'm pretty open to the "Arkancide" variety of conspiracy theory.