As long as they keep putting them on Hulu that's fine with me. I actually found the show on Hulu and have never watched it on "real" TV. The one time I tried to watch it on TV I couldn't find the time it was on (I think they had some sort of movie special on instead, but I wasn't sure about the time in the first place), but that week it showed up in my Hulu queue anyway, so I just went back to watching it online.
I wonder if this is a new option for shows. If the network that made them doesn't have time to air them they'll just send them to Hulu or other online venues. Of course, it usually follows that if they don't have time to air the show they'll stop making more, which would be sad for a show like Defying Gravity.