If you were wondering why we still hadn’t heard whether or not Supergirl will return for a second season, the answer is that Warner Bros. and CBS are still arguing about money.
Anonymous sources—so take it with the usual weight you give that—told The Wrap that even though CBS would like to renew the show, the three million per episode it costs is too much for the network. (Where all that money goes... special effects?) Add Supergirl’s decent-but-not-stellar ratings to the mix, and you can see why CBS is playing chicken with Warner Bros. over the renewal.
The Wrap also points out that the two sides could always compromise and put the show on the CW, the channel they own together. Of course, that would require a budget cut. Moving out of one of the major networks means losing major network dollars. And moving to the CW, which has always had budget-friendly TV, would especially signal a smaller budget.
Granted, even as almost all of us wondered why Supergirl wasn’t on the same network as Arrow and The Flash when it was announced, it would still be a strange move to make. It’s an option, sure, it’s just not the most likely one. It’s just that rare for a show to hop channels.