I used to have the old client running in the background constantly and was quite happy to update my addons whenever it told me to, even when I wasn't subbed to WoW.
But this Twitch thing? I have looked at all the settings and disabled all the crap I possibly can and made sure it doesn't start unless I actively chose to. So now I only update my addons when I remember to, like when noticing this thread. But first I have to start it and then wait for the client to update itself with all sorts of crap I don't need and don't want.
Sure, I could manually update my addons and bla bla bla, but really, look at the difference in behaviour, from both me and the client, between the two versions. Something is terribly wrong with that...