You can always modify the settings. it is not written in stone the. The rules are just some lines in a file.
But in secure the user should not have the permission to shut the system down with out root authority. Remember that Linux is multi user and you would not want everyone that may be running on the system to be able to unilaterally shut the system down. If it is a single user system why change the default permissions at all? It just makes any user need root to do system level changes.
The reboot/shutdown-behaviour is obviously unrelated to the file-permissions defined in etc/permissions.*:
I renamed permissions.easy to permissions.secure. But reboot was still not possible without root-privs when file-permissions are set to “secure” in Yast’s “Security center and system hardening”.
So something else is done which was not the case in 13.1/12.3 and probably earlier. Would be nice to know what it is and how to change it.
As a workaround I’ve renamed permissions.secure to permissions.easy and have set file-permissions in “Security center…” to “easy”.
I think it is misleading to establish an intransparent link between file-permissions-setting and reboot/shutdown-behaviour and at the same time disallow reboot/shutdown when it is explicitly set to “all users” with the same tool.