It's probably worth mentioning that Guessers also have negative utility from refusing others requests, coming from a culture where requests are generally accepted. If the actors are ethical, then this gives a preference towards guessing. In particular, you can imagine strategy where an unethical Asker is skilled at pitching requests such that the cost to a Guesser is greater than the gain for the Asker, but less than the Guessers penalty for refusing. By doing this the Asker "coerces" Guessers into agreeing. Recognising this, an ethical agent in a society of mostly Guessers will likely also take a Guessing strategy.