I believe there is no reason to feel insulted, because feeling insulted, is in itself, an insult to the many Filipino domestic helpers. There is nothing wrong with being a domestic helper, just as ther is nothing wrong with being an entertainer, a doctor, or an engineer.
These are all just jobs we do. No job is better or worse than the other. Not good. Not bad. Just different.
I asked a friend why he would feel insulted, and he replied it was because he is not a domestic helper. I asked him whether he would feel insulted in foreingers would associate Filipinos with doctors, even if he is not a doctor.
I rest my case.