I Don't Get It!

I admit to having a stupid/disgusting cigaret-smoking habit but, other than keeping the refrigerator open for extended periods of time, it is my worst vice. There is no alcohol, no recreational drugs, no meds, no lust for little girls or boys...in my life.
There is an excess of coffee consumed by moi because I am a genuine PEETS-a-holic and damn proud to be so.
My bravado and arrogance are counteracted by discretion exercised wherever it is still legal to smoke in public. Yet countless citizens still find ways to express their disapproval.
If dirty looks were dollars, I'd be a dillionaire.
The other day, someone at my gym, said "You smoke cigarets. Doesn't that defeat the purpose of going to the gym?"

I don't get it.
Does having a bad habit mean you are not entitled to having a good habit? Or was this man speaking with the entitlement associated with what are commonly known as "health Nazis?"