I hate people like this. I've grown confident enough to call people out on it. I was at a bar recently and was going to order a drink. When the bartender came over to me I blocked and it took some time for me to say what I wanted. She then said "don't call me over until your order is ready". I looked her in the eye and said "I have a stutter so it takes some time for me to get words out". I didn't apologize like I would have a few years back because there's nothing to apologize for.