Interesting. I haven't noticed this, but I'll pay more attention. I did learn a few tricks from hubs. For instance, you can add a divider between text capsules by using a photo hub. Another hub taught me how to make my links open in another tab without leaving my page by adding some HTML code. I am not an expert in HTML code, but wonder, if I knew more, could I at least dress up my text capsules (they have the HTML option in the upper left when you are in the edit mode).
I asked a question about this and an answer was that the HP creators want all of the pages to look similar and not look like spam. That makes the question of hub and hub premium even more interesting.