Well said, Matt. People nearly always have an "ends justify the means" disposition when it comes to telling the truth, it's refreshing to hear someone just say "tell the truth cause it's the right thing to do." I always tell the truth about my smoking.
At my last job, I had to take a "smoking cessation" course at my last job to avoid paying the extra monthly premium. Fortunately, the program stated clearly "you do not have to quit for this to count."
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Those were some funny conversations though! Rep: "How badly do you want to quit, on a scale of 1 to 10, with 10 being the highest?" Me: "Can I answer zero?" Thankfully, my current employer doesn't have an extra premium for smokers.
Regarding the insurance, the problem is this: if you knowingly provide false information to a company, that's fraud, and can void the life insurance contract.
Always be honest in those things. Why risk your family's future? Pay up, or find an insurer who won't charge extra, there are several out there.