Like Cedarhurst said, smoking is a physical harm and facebook is a spiritual harm, so they can not really be compared.
A person who smokes but does not use facebook, may be a frum guy, but he is putting himself in real physical danger, and may die young.
A person who uses facebook and does not smoke may live a long healthy life, but is putting himself at the satan’s door and begging for trouble.
And a person who uses facebook and also smokes is just a real winner all around