I am from Italy and I've never seen a house or a hotel there not having one. We have been used to use it since we are young and when speaking to other Italians abroad, the talk about "how can these people live without a bidet?" comes out a lot.
Must be tough for Italians to travel across Europe and feel like savages when using bathrooms on holidays? A bit like when I use the “hole in the ground” model of toilet in some countries I guess.