Are you still fretting over this?
First question is "why" ?
And as has been stated, if you don't like the way Google handles your site's indexing, then go ask GOOGLE to tell you why they are listing the way they are listing it.
What you are seeing has nothing to do with zencart, so there is no way that people on this forum can assist you.
This is a forum for ZENCART issues. There are forums and blogs for GOOGLE, so it may be a good idea to post your concerns on those forums.
Sorry to be so blunt - but I don't see that there is any problem with the way Google is returning your SITE result (different from PAGE-SPECIFIC results) and the likelihood of someone putting in your site URL as a search term are as remote as someone making thirst-quenching tablets with the instruction to "take two with a large glass of water..."