notpashut,
your logic is a bit off,
smoking is not comparable to ruchnius things as we know smoking kills because we see the results and have satistics to prove it
the arguments against rabbonim banning things are either
that the things they are banning arnt harmfull to the neshama (wich in most cases is pretty hard if not impossible to prove either way).
or that banning it wouldnt be an effective way of taking care of the problem