Expressing Gratitude
Before we judge this woman's choice of a tasteless T-shirt, perhaps we should thank her. We've often been caught off guard by someone else's emissions, leaving us no opportunity to escape the impending olfactory danger.
In this case, the lady ensures that there won't be a "silent but deadly" situation, sparing us from nearly choking to death without any prior warning. After all, they say, "he who smelt it dealt it."