I have a WooCommerce shop page and in the S2 Retstriction Options Panel the Page Level Restrictions dropdown is set to Require Level #1 or higher. The page id is also listed on the Page Access Restrictions S2 page (for both Level #0 and Level #1 - not sure why for both - was done by a previous developer)
The site has paid access only for a specific set of pages - all defined individually.
It seems to work fine for other pages.