Still, one questions remains: what would stop somebody creating a confirmation bot that will charge a tax of 1000 tokens? The fastest bot will take the fee, isn't it?

The fastest bot takes the fee, but the protocol only awards 1 token as a fee for a confirmation. A bot can't take more than 1 token per conf.

It's not the bots who decide where the tokens go, it's the protocol. Bots that don't obey the protocol will be ignored by bots that do obey the protocol.

Another way to look at it is that if someone builds a bot that doesn't obey the protocol, that bot won't be part of Pocket - it will be creating a fork of Pocket. People can follow that fork if they want, but if there's considerable mass already behind the original Pocket, my money is on people sticking with the real thing.