Simon, anthropic probabilities are not necessarily the same probabilities you plug into the expected utility formula. When anthropic games are being played, it can be consistent to have a ~1 subjective probability of getting a cookie whether a coin comes up heads or tails, but you value the tails outcome twice as much. E.g., a computer duplicates you if the coin comes up tails, so two copies of you get cookies instead of one. Either way you expect to get a cookie, but in the second case, twice as much utility occurs from the standpoint of a third-party onlooker... at least under some assumptions.

I admit that, to the extent I believe in anthropics at all, I sometimes try to do a sum over the personal subjective probabilities of observers. This leads to paradoxes, but so does everything else I try when people are being copied (and possibly merged).

Regardless, the question of what we expect to see when the world-crusher is turned on, and how much utility we assign to that, are distinct at least conceptually.

And if turning on the LHC or other world-smasher causes other probabilities to behave oddly, we care a great deal even if we survive.