I worked at home depot for five years. At one point, during maybe year 2 this older guy in his late forties started making fun of my stutter. This hadn't happened since at least middle school, at least to my face, so I was completely stunned. I filed a complaint with HR and he formally apologized to me the next day and not a peep was made from then on. This is harassment and it is a huge liability for public embarrassment. What if you contacted local news and they did a human interest piece? The company would look like a joke. Businesses don't want to look like a joke and will therefore be very attentive about this type of harassment. Tl;Dr Talk to HR.