Deny Like right has no effect on admins

Reproduction steps:

• In Administration > Like uncheck "Always display Like button"
• In Administration > User rights, deny Like right to both XWikiAdminGroup and XWikiAllGroup
• Go back to the home page

Expected result:

• the like button should not be viewable by the Admin or by any user

Obtained result:

• the admin user is still able to see the like button, and even to use it. The button is not visible for guest or for a regular user.