D&D wasn't really "not accepted" so much as noone played it. While "official" games did occur (L5R, BESM), there were extra tables and even non-RPG games available for play. If someone, for example, wanted to play D&D, they could set up shop and run, even if it wasn't an "official" game. I know that at least in 2003 there was a D&D game going...
PezCat