One of the main reasons I (and I assume many others) take drugs is boredom. I live in a quiet suburb, and its a 15min busride to anywhere. I can go to the cinema, the pub and drink soft drinks, a meal, play some footy etc. However I find that these things can only entertain me for a short time, whilst i'm not sober I can find enjoyment with longevity. Reading that back it seems quite sad, but it doesn't make it any less true
Its also my social group. Although this would have been more true a couple of years back, me and my friends have gotten into the mindset of 'sober means boring'. Its not always true, but is alot of the time. I think if you live in London, or Manchester etc the ways to entertain yourself are going to be myriad, and so you are less likely to turn to substances to alleviate boredom. Out here in the sticks, the question isn't 'where are we going' but 'what are we doing?' if you see what I mean.
I think drugs appeal to those of use who are less health conscious. I've never worked out, I smoke, drink, use cannabis (and have had many binges on coke, E, shrooms, Special-K, acid, and others in my time), eat a diet of ****e etc. I've just never worried about my health or how the things I do can affect it. Others must be like me surely? I've always taken the jaundiced attitude I'm going to die anyway, so why bother

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It used to affect my work and family life. Nowadays I'm much calmer and work, commitments etc, always come ahead of smoking a joint or whatever. That wasn't always the case, and is probably the main reason many are anti-use. It can take over your life. It becomes you, your definition.
Its not immoral, its a personal choice. I think it becomes immoral when your running down the high street at 3pm pished off your trolly starting on old grannies (not that I've ever done this lol). As long as it does not affect those around you to a great extent, its ok. But as a personal choice it should not cause other people bother, its then that it becomes immoral. I'd argue for the legalisation of cannabis because its never resulted in a fatality and isn't going to lead to violence. The same cannot be said of crack or heroin, and so these need to remain prohibited.