Lots of places. I did bring this tradition to my home from Thailand. I keep a small towel next to the toilet to dry myself, that I change every week or so.
The main downside is that modern toilets nowadays are wall mounted without any exposed pipes, which makes it impossible to install a bidet without making holes in the wall...
Have you never heard of a blind spot? We are all different people with different experiences. --> fails to describe what a blind spot is. Although the meaning can be guessed by context, it's important enough to state directly, as the woman's ignorance of it is what causes the altercation. Here the artist should have focused on the original premise: how can you question how another person doesn't know something, when you yourself have blind spots?
Another big miss: the silly ending which subverts the intent of the comic and leads to people wandering off (see comments about toilet paper below) when again it was possible to highlight the information problem.