I may be wrong(correct if I am) but it seems the argument is a smoker usually = an addict whereas a drinker and gambler may or may not qualify for that label.
My mother was both an alcoholic/problem drinker and a cigarette smoker. The former resulted in certain behaviours and when she hit her mid-late 60s physical issues.
My father on the other hand can have the occasional cigarette if offered without the need to buy a daily or even weekly/monthly pack. He is partial to a glass of red wine but alcohol has not had the profound effect on him that it did my mum.
It is reckoned that addictions often run in families (nature or nurture or a combination of both?) . When it comes to my grandparents I know little of their possible addictive tendencies. Especially as my paternal grandfather died before I was 3, never met my maternal grandfather and my maternal grandmother died just before my 5th birthday.
What I do know is that my brother and sister both have moderately addictive personalities . Both smoke. Both have or have had a fondness for alcohol. Additionally my brother has decades of doing illegal drugs-mainly cannabis and occasionally other substances.
I have never smoked or done illegal drugs. A lot of that is not because I am better than my siblings but because I was so ostracised I never had the peer pressure in my formative,teenage years. I also hardly ever drink but have a track record of binge drinking(drink a lot very quickly to crash out) when faced by overwhelming stressors.)
If one argues that something is partially genetic should we then really be stigmatising people for it? What of other problems that are probably partially genetic within the area of (mental) health problems?
Do we go down a socially undesirable path in stigmatising people who may well have a partially genetic health problem?
Was such thinking not the catalyst for the eugenics movement of the late 19th through to the mid 20th century?
Do we really want to live in a world like that?