Yes, this can happen alot, especially with family you don't see often. It has with me, anyway. My philosophy has been that if the person is someone I care about and who cares about me, I'll take the time to educate them. Some people though are just too ignorant, or they have preconceived notions about MS that they can't get rid of. For rude strangers, I try to come up with something pithy that they won't forget.