I have to be honest with you all, I don't really support banning tobacco in this way. Sure, I hate tobacco and don't think anyone should use it. I do however, support peoples rights to use it if they choose.
Now don't get me wrong, when Michigan banned smoking indoors I was very happy the next time I went to some of the bars. I know this is a little different than sporting events.
Also, I never once had a friend that dipped for any reason related sports. If anything, the only people I knew who ever did it to be "cool" or follow a trend, it was the girls in high school smoking because it was glamorized in the movies.
If it does get banned, I hope it is not banned by the league. I hope each team makes their own no tobacco policy on the field so that it is not a totalitarian decision by the league.