Pineapple on the pizza is a cardinal sin in Italy, you know, the place that invented pizza? That should tell you everything. And yes, depending on the region you could even get beaten up for this shit.
I don't get the hate for pineapple pizza. Sweet and salty things often pair well together, my grandmother likes to cook pineapple in her sweet and sour pork as well.
It's funny how the maid was willing to sacrifice the heir apparent to be beaten black and blue, just because her position in the family had always been low. They forgot that they could also confront the madam rather than having the daughter sacrifice.