In the Commerce theme, there is a search bar and shopping cart close to the top of the page, but not all the way at the top. I believe this is to make room for the Control Panel bar if one has permission to see it, but for non-admins, there simply is nothing there.
This means that when you scroll down far enough, all elements will show up above the aforementioned search bar. I'm not sure if this is intentional, it just looks odd, so I'm reporting it just in case.
Steps to reproduce
1. Login as a regular user and go to a Commerce Site
2. Scroll down until elements go above the search bar, and you will see them at the very top.
Expected: The search bar will be at the very top edge of the page for non-admins
Actual: The search bar is not at the top and leaves a gap.
Compare this with admin-banner.jpg - this is why I think there's a gap for non-admins, since they cannot see the Control Panel bar.