I am sorry if I my answer was not as elaborate as it should have been. Sitefinity does not have the concept of folders (the closest thing is a group page). So, when you say that users won't remember it and find it burdensome I am assuming that you mean that users that create new pages will forget to set "Deny Anonymous".
However, this property is inherited in Sitefinity. So, for example if you create a page (or page group), name it "Intranet" and set it "Anonymous access" property to Deny, all the pages under that page will inherit this property - in other words, anonymous users won't be able to access any page under the "Intranet" page.
I hope that I have understood your question correctly this time and that you will find this information helpful. Let us know if there is anything else we can do for you.
the Telerik team
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