because the remake is good, and it would be neat to have the very slight differences in a silver version, that's all.
in fact, i'd be willing to help out make a parallel version once this is nearing completion, if necessary.
since the only main differences are the capturing:
[there was a url to bulbapedia specifying the different ones, but i cant post URL's yet =/]
and what wing you get to capture the first legendary bird. and i think its important to keep the trading aspect in a pokemon game =)