[mwfunk]

You're not expected to answer the question, just say "not bad" or "pretty good" and move on.

[int_19h]

Indeed. The problem is that it's kinda hard to make yourself do it and not come off as insincere when you're not culturally conditioned to do so from a very early age. You can learn, but it still requires a conscious effort.

[KC8ZKF]

Add "You?" to be polite.