Health: Maybe the people you know are of a different type than the people I know.
And I don’t have children in the parsha of shidduchim yet, but I wouldn’t want my daughter or future grandchildren to be exposed to 2nd hand smoke. And I definitely wouldn’t want to be supporting a thousands-of-dollars-a-year harmful addiction, no matter if he’s the “best boy in Lakewood” or not! I’d rather take a 2nd or 3rd “best” non-smoker, if it’s the choice between those two. My humble opinion.