Even though I can understand the frustration, I find it sad that so many people dismiss this show as "yuri bait", 'cause it's a lot more than that. It's actually grown to be one of my favourite shows, especially thanks to the second arc of season 2 and the music, which I really enjoyed.
I can't really get mad at Hibike, because it was actually what led me to discover yuri. I was still pretty new to anime when I first watched it, so I wasn't familiar with this kind of fanservice(?) and I legitimately thought they would get together... So I was rather shocked by the revelation of Reina's crush. Well, realizing that my "just kiss already!", which I had thought multiple times throughout season 1, would probably never happen, I went ahead and searched "anime where girls kiss", or something of the sort, and ended up finding Sakura Trick (which sure quenched my desire for kissing lol).
For the record, I don't think that the fact that they don't get together makes Kumiko and Reina's relationship insignificant, or "bait", but I think @schuyguy's post above explains it better than I could.
And @Pulsar, how can you judge a show you haven't even watched?? This is exactly what saddens me about all this "yuri bait" talk: people criticizing a show (and sometimes even the whole studio), based on only one part of it and often without even having watched it themselves.