Anonymous cannot see cart in cart page I need to debug an issue and don't know how to start.

If I'm logged in the cart works just fine but, if I log out and put something in my cart I see the object in the cart widget but not my cart page.



And this is the markup in the page.



I need a hint to understand where to start searching the issue because the cart page permission and the view permission I think are fine because I see them, but the content is wrong..  

If I go in admin/structure/views/view/commerce_cart_form/edit page and I insert the order ID, I can see the right cart displayed in the right way.. 

Where can I start to debug this? 
Do you have a clue to where can the bug be?

I tried to put a couple of prints in the view header and the cart page remains blank. But why is the empty cart sentence not displayed if the order_id is empty?
And why 2 different carts views in the same page act so differently?
My guess is you're experiencing a common issue with product permissions due to a relationship you've added from the line item to the referenced product. Open your View's advanced settings fieldset, and in the Query settings menu disable SQL rewriting. This will bypass the normal entity access check to see if a customer has the permission to directly view the related product data, which is fine for this View since we know the products in the cart will always come from line items the customer has created through Add to Cart forms.

See also: https://drupal.org/node/1276450