Except that those trillion pages have little incoming links ~ so they have no "juice" or "pageRank" to pass. Target has 267k incoming links then redistributes that via internal links / a while ago people started "link sculpting" using 'no-follow' in the link <ahref> to take all the homepage link juice and pass it to what they perceived as their better converting pages.. but google has since come out and said that wasn't a good thing to do...
Right. Having extra pages, versus extra content, is not specifically beneficial. If that were the case, other sites would fill themselves with specious stuff like empty search results pages.
