Keith of Hertford,
Thanks for the reasonable post. Here are some hypothetical questions for you:
If you ended up in court for some reason, and the judge started by asking you if you were a Christian, and you weren't, would you feel that the judge was asking you an inappropriate question? Given that there are large segments of the population who have proved they are not tolerant of non-Christians (you might just have to take my word for that), would you feel worried about the level of impartiality the judge would bring to your case? Mind you, I'm not saying the judge would necessarily be lacking in impartiality, but having been asked the question, wouldn't you wonder about it?

Another example: You go into the emergency room with a serious injury. The first thing the doctor says is "Let's pray for your return to health". You then say, "I'm not a Christian". Are you left wondering if you have just insulted someone who is about to cut you open or sew you up, or whatever? Do you worry about how rational and tolerant this particular person is? Again, keep in mind that many non-Christians have been discriminated against - if only by being insulted - in large or small ways for their lack of belief.

Of course I don't get upset when people talk about their faith and they don't in any way have my fate in their hands. If they do have my fate in their hands, should I lie and pretend to believe so I don't upset them? How do I know, with strangers, who is going to be intolerant and who isn't? If they are wearing a cross or a veil or some other outward sign of belief, again, no problem. If they ask me to join them in praying or ask about my religion, there's a big problem, one of perception if nothing else.