I get the same thing. When I go to "Change plan settings"
Then "Change advanced power settings"
and then attempt to change the "Yes" to a "No"
I cannot. Though it is ill-advised, I don't have a password on my account so the password is not prompted on wakeup. Also, I don't have my system set up to ever go into sleep mode. I changed the setting in "Put the computer to sleep" from "Never" to "10 minutes" and the option to change "Require a password on wakeup" to "No" was still not available.
I have not checked to see if any difference would result were I to have a password on the account.