I think a lot of us have experienced this. And of course it’s annoying. But I wouldn’t stress about it too much. You can’t control what happens outside of your power. What you can control is how you’re dealing with their response. No one, or at least very few act extra nicely because they want to hurt your feelings. Their generally trying to be nice because they think it helps you. Or they might do it as a coping mechanism because they can’t deal with what is frankly a slightly awkward silence, or at least it may seem awkward to people who are unfamiliar with stuttering. So don’t take it too hard on yourself.