You do not need SEO Urls.  I would argue that even this is out of date.  When is the last time you saw a URL (of a properly set up ecommerce site) in (eg) Google? Here is an example with no setting up, just an out of the box install of our osCommerce.  Wheres the URLs ?? You could argue, and I would wholeheartedly agree that "Friendly Urls" matter. Take for example a radio advert or a printed leaflet, which one of these is more easy to remember;