A few years back, I was in line at the grocery store. A woman in her early 20s was the cashier. I had some blocking, and she tells me in a slow voice, the way you would talk to a toddler, "use your words". I showed much restraint that day. I did inform her I stuttered and the rest of transaction was awkward obviously. Edit: I was in my mid 30s at the time, so it wasn't like I was younger than her.