I felt that this was in between a bug and a feature request. I don't know if it's intended behaviour or something the developers forgot. I try to clear the "new" badge on the store button by clicking on all new content in the marketplace (which I'm not a fan of). It's really hard to do this now. The sale icon cannot be removed which is what led me to the assumption that this is not intended behaviour. I believe a simple toggle in the video section of the settings to disable "Notification badges on Store button" would suffice.