I am sure if you (LastMitch) live longer, you'd live happier.
Until that person is suffering from an incurable disease, at which point your logic is, at best, flawed.
Coming from somebody that is 21 and completely tea-total, you can look at drink/smoking etc from two points of view. Yes both are bad and put pressure on the health industry etc and may harm the body. But on the other hand it is somebodies way of relaxing and chilling out in the evening.
I for example easily spend 20+ hours a week playing video games when I'm not at work, this isn't the best for my health and damages my eyes over time, but it is what makes me happy and thus I do it to chill out. My parents like to have a glass of wine in the evening to relax, they don't consume excessively and its perfectly acceptable.
You for example Michael have alot of interest in sports it seems. While that is all well and good we have recently seen a professional footballer collapse from a heart attack, die and be revived, and live on when they are seen as peak physical condition. While the argument there that sport is good it can also be just as bad for you in terms of body overworked etc.
Everything has its downsides, its all about opinions.
TL:DR - Its all opinionated and nothing more.
Edit - Clarified footballer further, I am referring to 'Fabrice Muamba'