As it said in Documentation for Page Restrictions:
'Edit' restrictions are not inherited from the parent page, only from the space. In a space, the 'Add Pages' permission governs both the creation and the editiing of pages. See Space Permissions Overview.
It seems to be inconvenient for limiting access within one space. For example, there is a Space PROJECTS which includes pages related to different projects. Each project has its own project team and its own group in Active Directory. Viewing the project is not limited to anybody, but the editing should be. That is why we need to limit restrictions on the Page level.
'View' restrictions are inherited from the parent page.
Please consider ability to inherit 'Edit' restrictions from the parent page.
Another nice-to-have feature is to improve Page restrictions mechanism. Now there are only 'View' and 'Edit' actions are supported on Page level. It would be nice to have 'View', 'Add', 'Remove' pages, 'Add', 'Remove' Blog posts, Comments and Attachments restrictions on Page level as well.