On the surface, it's a harmless question. You're supposed to answer, "Just fine, thanks." But my first instinct is to answer honestly. I doubt if the host wants to know about my sucky day; that my foot hurts and I just backed into another car. What if I just came from the doctor having learned I have a terminal disease?
Less intrusive but still annoying is the common wish people bestow upon strangers: "Have a nice day." At least with that one, there's no opening to discuss my sore foot.
A lot of people don't like "Have a nice day." It doesn't always ring sincere. I've been tempted to answer "Have a nice day" with, "Too late!" But I never have. When you think about it, even if it’s not sincere, the person saying it wouldn’t necessarily want you to have a bad day.
While sometimes irritating, I think I'd rather have these courtesies than the grunts of surly, snarly wait people and store clerks found, for example, in some east coast establishments. They don’t even say thank you, let alone "Have a nice day."
Given the choice I'll take false friendliness to open hostility.
A friendly thank you or even "Have a nice day" shows that a server at least has good manners. And good manners help to keep society civil, which judging from the House of Representatives (brought to you by the Tea Party), is not a bad thing.
So now that I’ve made a hostile comment about the Tea Party, I will sign off. But before I go, I really do hope you have a nice day.