There is, at least in the United States, a stigma associated with sobriety. In many ways it is more accepted in the workplace to be heavy binge drinker than someone who chooses a life of sobriety.
People easily laugh off or empathize with hangovers like a rite of passage, but seemed shocked when they learn you don't drink.
There are a myriad of reasons someone may choose to be sober. They may choose to be sober for health reasons, because of their religion, an addiction, or simply because they do not want an altered state of consciousness.
Modulating ones emotions, actions and feelings is so common that one can feel like an outcast if they do not partake.
This is not to say there is anything inherently bad about alcohol or substance consumption for most people, but to judge someone because they choose not to alter their own chemistry seem backwards.
It is hard to image we can address the stigmas surrounding recovery and addiction if we can't even get comfortable with someone being sober.