Dec. 10 is International Human Rights Day. I often meet people who do not realize that refraining from using fragrances in the presence of someone with sensitivities is required by law - the Canadian Human Rights Commission has good material on it.
Some act as if it's their right to wear scents -- not true, no one has the right to injure another, and scents do harm to vulnerable people. Fortunately most people comply and are supportive. Unfortunately it only takes one to make an entire assembly unsafe by their fragrance. So I had to stop participating in the choir I loved because there was always someone who forgot or didn't understand or refused to comply or didn't yet know. Family gatherings have had similar unfortunate results and I experience a lot of social isolation.
Fortunately, it's getting better known, because more and more people are acquiring sensitivities, I expect because a generation of us (or two) have mercury amalgams in our mouths eroding our immune systems generating allergies and sensitivities, autism and alzheimer's (thanks, Sue, for the link) and other illness. Staggering, a whole population poisoned by preventable practices. Gotta love alliteration! :-)