@Rahadian0 The host told you she was asking as she's had issues with this in the past. It's not racial profiling, it's just her knowledge about different cultural customs that led her to mention it. There are many places in the world where people naturally do things differently and hosts try to be aware of that so they can ensure that the guest/host relationship goes smoothly.
Lots of Asian countries, for instance, have bathrooms that are "wet rooms." It doesn't matter at all if you flood the floor or splash water all over the place, but many of those guests don't realize that doing so in a home with a wood subfloor can cause extensive and expensive damage. So hosts might mention that to guests from those cultures.
Many places in the world have different bedding styles- they don't use top sheets, just a duvet. Guests from those cultures are often confused as to what they are supposed to sleep under and on top of. Most guests from those countries are white- if a host explains to them that they are meant to sleep between the sheets, not on top of everything, that's not racial profiling, it's just being aware that not everyone has the same cultural habits, and educating the guests as to how things are done where the host lives.
I can see where you might have taken offense, but I seriously doubt the host intended it like that. She has no idea whether you just recently moved to Australia from a culture that squats on the seat. And if she had some predjudice against Asians, she wouldn't be accepting their bookings.