I don't like that kind of behaviour from ubuntu, such as offering restricted drivers and suggesting for the user the installation of proprietary codecs -- I've been told it does that, I might be wrong. That's supporting the use of proprietary software, which I don't think shouldn't be the goal of any GNU/Linux distribution. In that sense I only wish ubuntu has less support for proprietary software, not more.
The thing that should attract people into GNU/Linux is the free software philosophy. If they're going to use GNU/Linux without even worrying about what free software is, then I don't care at all if they are using it or not. Why should anyone involved in free software development care about people who doesn't care about free software? Why should I care about someone who doesn't even make an effort in trying to stay away from non-free software, unless they have absolutely no choice?
Ubuntu doesn't ship with Flash to the convenience of the users who want to use free software -- so they don't have to uninstall it (or worse, use it without realising it's non-free).