I heard you, though I pretended not to. You rolled your eyes and mocked me to the cashier at the checkout as I walked past, pushing my shopping cart. "That's just the most ridiculous thing I've ever seen," you said. "What a sense of entitlement she must have." You were mocking me because I have an invisible disability and am assisted by a service dog. You speculated aloud that I "probably just ordered that vest online". You were especially convinced of your righteousness because my dog is a little chihuahua, and as you loudly elaborated, you "have no idea how on earth a dog like that could possibly be a service dog." But you were wrong. In fact, I have an excruciatingly painful disability, that you cannot see and know nothing about, that makes everything I do ten thousand times harder for me than it is for you. I have been assisted by a service dog for close to a decade now, and sometimes her assistance is the only way I can manage through a day. That's MY business, not yours. But it might interest you to know that there are hundreds of tasks that small, unconventional- looking service dogs perform for their humans (eg, medical alert, seizure alert, blood sugar alert, ptsd assistance, allergy alert, OCD assistance, reminder cues, fetching assistance, heart/ respiration alert, to name but a few). You allowed your stupid self to turn your own ignorance into a blade with which to cut me and people like me. After you left the store, the cashier came over to me and apologized for your despicable behavior, and told me how obnoxious you always are in that store, and we laughed about your stupid face.