Usually a five-pointed star would indicate an opportunity to "fave" an episode, with no social aspect.
Calling this button “Recommend”, by contrast, makes it seem as though clicking it will make something social happen. But if something social did happen, I couldn't figure out what it was. For example, no new tweets appeared on my Twitter timeline as a result (it would have been a kind of creepy sneaky way to do it if it had though).