What it fails to examine is the fact that smokers are much more likely to be out of the workforce at an earlier age, meaning they earn less money and pay less taxes. The total net costs of smoking related diseases on the economy is much higher than their direct medical costs. Moreover, the burden on insurance providers is higher too, given the loss of premium payments and the lack of Medicare reimbursement for younger cases.
Additionally, the study was conducted a decade ago. Smoking related health care costs have continued to rise, and a new study with the exact same flawed methodology would nevertheless likely yield different results.