Even alcohol is good for your heart: alcohol in moderation can help prevent heart disease but thousands are at risk of alcohol death say doctors . Everything is good in moderation, but addictive stuff gets commonly abused. Regarding nicotine the carriers are harmful. So overall effect is negative. Not that people care.
I guess this depends on what your definition of "addiction" is. There currently is no universally accepted definition of the word.
In medicine, the terms "substance abuse" and "dependence" are used. I don't believe either of those are correct in applying to my current personal use of nicotine. (Note the definition of Dependence: "Substance use history which includes the following: (1) substance abuse (see above); (2) continuation of use despite related problems; (3) increase in tolerance (more of the drug is needed to achieve the same effect); and (4) withdrawal symptoms.")
I would equate my use of nicotine as similar to other pharmacological drugs. Some people need anti-depressants to get through the day. I use nicotine. I see no problem with that.
Which carriers are you speaking of?