Not a pretty solution, but resetera images are automatically corrected by bots after you post now. Ideally there'd be a way to just not copy over the alt information but I couldn't find it in the javascript.Awesome!
edt: tweets and youtube videos are now copied over in resetera posts.
I can't help but feel this will encourage more lazy posting though, with people just copying stuff from Era without adding anything themselves or citing the original source. We need more original stuff if we're going to attract new members.