States were clearly given the right to tax as well not simply the federal government. I would stop eating the taco and buy some ground beef and a shell and make my own. Failing that I could, if I was so inclined, make the shell from corn meal, and raise my own cow. Hence the term no unavoidable tax. The states are not restricted from levying taxes, however congress is restricted from mandating an unavoidable tax and any taxes they do levy must be uniform.
If I understand correctly, that would be an argument between direct and indirect taxes. Only direct taxes are unavoidable, indirect taxes are imposed upon activities and are avoidable. That being said, if tobacco products are unhealthy they should be illegal, like crack and pot. Milking the tax cow from smokers, under the guise of health issues, while ignoring the issue of obesity is disingenuous...to say the least.