Jane Lake and Children!
I read an article in Time magazine about how having children makes you less happy overall, but the occasional moments of wondrous joy make it all worth it. They then compared it to heroin.
I fully agree with this based on my experience with kids, but I would caveat it to say that you have more control with kids. You don't have to take them to a restaurant and keep telling them to leave the sugar alone. You don't have to take them into a fine china shop and tell them not to touch anything. As long as kids are in a controlled environment meant for kids, they are great and everyone is happy!
Heroin (and all recreational drugs for that matter) is just stupid!