A good article from Fred's Head which asks the question of the title. The points made are valid ones IMO, particularly the point about how the public in general views us. As a blind person you are likely to be the only blind person John Q Public ever meets. This is why being polite (no matter how vexing the person) is so important. This is not always a success- there have been many times where I have simply not been in an educator mode and ripped someone's head off. I always regret this, as I know my behavior directly reflects on my blind brothers and sisters. Diplomacy has become easier for me since being involved with the NFB, but there is always room to learn.
On a side note Through Our Eyes is an outstanding podcast on blindness. During their next show (4-21 8pm EST) they will be discussing the International Braille and Technology Center (IBTC) the place I would live if only they would let me set up a cot. If you don't know about the IBTC, or simply wish to hear the discussion I suggest tuning in.
The National Federation of the Blind