Why do seemingly descent people, go off the deep end when they leave the Church?
Nobody "goes off the deep end". That's a caricature that believing mormons latch on to due to a misunderstanding of how perfectly normal, healthy, non-mormon people behave.
Can't common sense, (you don't need the Church for that) dictate that smoking, drinking, cursing, drugging, humour about drug use etc etc..is not only foolish, but hurts noone but yourself?
- Smoking hurts, yes. Everyone knows that, and the people who choose to do so anyway are no worse than people who know that a poor diet is bad for you but eat poorly anyway.
- Drinking alcohol in moderation and with a healthy understanding of its effects is harmful to no one. Abuse of alcohol, like abuse of anything else
, is harmful, sure, but is not unique to non-mormons. And most well-adjusted human beings have no trouble using alcohol responsibly.
- Humor about drug use is also perfectly fine. If you can't laugh at something, it's not worth living.
- Cursing shows a finer grasp of the subtleties of language use than stilted, sanctimonious derision of cursing shows. I give a big long speech explaining what precisely I think is wrong with a given situation, sure. Or I could just say "Balls," and my tone meaning would be perfectly clear to any listener. Many of us here can speak and write circles around many of our peers. But we don't disdain profanity when profanity is precisely what we intend to say.