What a weird thing to say. So in her world, only kids refuse to eat certain foods they dislike, and adults eat whatever? How utterly strange.
She seems to be lacking a brain to mouth filter, too...(Like a kid

) Really, who says something like that to a customer? I am not at all of the mind that "the customer is always right", but I do think "the customer who makes a respectful request deserves a respectful answer."
However, I do think you would not be lying if you called it "intolerance".
If a food makes you nauseated when you taste it, then you /are/ intolerant of it. Intolerance doesn't have to mean that you break out in hives or can't breathe. If it is bad enough that it makes you feel sick, it's intolerance in my book.
But I'm not saying you /have/ to call it intolerance. If you don't want to eat something just because you don't want to eat it, that is your right and nobody should be a smart aleck about that.