For example, after years of avoiding it, I have quickly settled in to the caffeine routine. Coffee in the morning, occasionally a soft drink in the evening. While this is hardly risky behaviour, it is drug use.
I personally would consider using different drugs more regularly. Jet lag really can be a killer, so I would take something when travelling if there was a good option I was aware of.
Personally I am strongly against certain drugs being prescription and unavailable to informed individuals. It makes it seem like these drugs are entirely safe when prescribed by a doctor and unsafe if people get them through other means. I have some heavy painkillers that were legally acquired but not prescribed by a doctor, and I use them in a very safe way for my occasional intense back pain. I know many people on the same pain killers who take them in an irresponsible way as prescribed by their doctor.
It is a topic that I think we need to try and avoid looking at it with such a narrow vision. I also think a lot of illegal drugs are no more dangerous than legal drugs, but that is another topic.