Delete cookie just before render I am trying to hide the fact that I have a Drupal site (as much as possible).  

The idea is that if a would be hacker (I am not talking about some ninja that could break into the pentagon) looks at the site they would not be able to (easily) see it is a Drupal site.

Most of it is done - I just don't know how to delete some cookies set by modules.  In specific I want to do this for anonymous traffic (clearly someone that is logged in already knows they are on a Drupal site).  The cookies that I want to delete would not affect the site - it is related to two admin modules.

I tried a couple of hooks - the last one was theme_html_head_alter - but nothing works.  This is the code I need to insert somewhere - just not sure where?

if (!user_is_logged_in()) {
   user_cookie_delete('DrupalModuleFilter');
   user_cookie_delete('Drupal_tableDrag_showWeight');
}
Did not find the answer (I did try hook_page_alter) - but I realised I was not focusing.  I want to hide those cookies from anonymous users, but those users will never access the admin section, so the two cookies I am trying to delete, will never be set.