Most people are very considerate, others not so much. But what are you to do but just be yourself. The other I stepped into an office and started to talk to the man behind the desk, there was a second person in the room who jumped up and told me "hold on there son. You don't have to be nervous." I stared at him blankly and told him " oh no I'm not nervous. I just stutter." I felt so bad for him, he blushed all over. Even if someone says something you don't want to hear, most of the times it's unintentional as you said due to lack of knowledge about stuttering.