Other people's opinion of my birth plan...

Sa
Am I the only one who thinks it's insanely rude to tell someone they will not stick to their birth plan? I'm not talking unrealistic expectations, either. I would like to give birth in the hospital with no Epidural or other pain meds, and when I tell others, I am CONSTANTLY getting laughed at and told "you'll change my mind" and "there's no way you'll go through with it."
Not everyone reacts that way, of course. I just find that extremely rude. Am I overreacting?