I guess its medical, if not, philosophical
That is true. People are very much influenced by what is around them and how they are raised.
Being around people you like and are good for you
When stimulated, the brain stem's sneeze center orders muscle contractions from esophagus to sphincter. That includes the muscles controlling the eyelids. Some sneezers even shed a few tears. Perhaps people close their eyes while sneezing to prevent the expelled particles from entering their eyes,