Many (maybe even all) series on Crunchyroll (perhaps Hulu as well) for example have no subtitles for the opening and ending.
Why is this?
This was stated by the Support Manager??(or is that just a forum title) of Crunchyroll:
This involves getting the rights to the songs that are used as opening and endings for each show on the site.
So not only when licensing new simulcasts would we be going after the show but also the opening and ending songs.
A lot of bands are reluctant to let their songs be licensed as this means that the translation presented is -THE- official translation of the song.
He also backs that up at: http://www.crunchyroll.com/forumtopic-758633/are-cr-subs-lacking-a-bit
So he does seem to be a staff from Crunchyroll.