Why do people think they need to be under the influence of something to have fun, is probably because their brain isn't producing dopamine naturally anymore, because they've gone and introduced drugs or alcohol to make them feel euphoric. Sure, being buzzed sounds like fun in theory, but would anyone want to sacrifice how awesome an orgasm is, by using a drug that gives you one, only to take away your natural ability to acheive one? I doubt it. So... if happiness and peace of mind are sacred to anyone, then giving yourself a few months, or a year, or more... or forever, if you're able, to cleanse your system and allow our bodies to return to their awesome natural, healthy states, producing their own highs and lows without artificial stimulation, is a beautifully selfish thing.
You just can't explain this stuff to some people, they either get it or they don't. Happiness is no ball and chain.