Yeah they got away with one. There isn't much anyone can do about things like that. It's going to happen.
There were more than a few occassions when Ware was basically mugged and it wasn't called. That's just the breaks with football.
If I'm remembering correctly, somebody in the offseason had holding-call-per-rush statistics for each team for 2012, didn't they? I seem to recall the number of Dallas calls per rush being ridiculously low, considering Demarcus Ware was one of the rushers. Can anybody corroborate that?
Either way, yah, it's something you have to just live with. All you can do is what JG did this week, which is try to make a big deal about it when it happens, and then (hopefully) quietly bring it up the week after so the league is aware that it's something you're watching closely.