I don't care about the numbering and such. But I do in fact feel weird about buying a physical disc of a game that may not be playable ten years from now. Now if the gameplay isn't tied to servers and such or you can play splitscreen or LAN play, then maybe. I'd still do neither personally, and I'll probably never play the game.
I don't know. I loved UT growing up and I have a special place in my heart for Cliffy B and what he does, so I wanna show my support. But where I'm at in my life, I have no interest in playing games like UT. UT in my youth was fun because I was playing friends/classmates. I don't have that anymore, so it is not in my interests.