Well, whatever it is, when I was a toddler my parents mentioned to my pediatrician that I loved eating hot peppers (apparently I would just grab them off the shelf in the grocery store and chow down. It was a bit of a problem for my mom because I wouldn't wait for her to pay, or so goes the story she likes to tell). The doctor told my parents that I don't have receptors to detect capsacin. I haven't had it independently checked as an adult. Maybe they were mistaken or my parents mis-remembered what they were told.
Regardless, I don't think I've ever experienced what you refer to as feeling like getting maced while sneezing or laughing. I haven't been directly maced before, but I have been in a crowd that got pepper sprayed. It burned the fuck out of my eyes and lungs, but I didn't notice it anywhere else.
Yes, of course it is.
Like any privilege, having 'pretty privilege' doesn't mean your life isn't difficult or that you don't have problems. It just means that your looks aren't one of the things contributing to those problems/difficulties.