If I had to guess, it is similar to why people spend small fortunes on diamonds - despite being a horrible financial decision and having superior/cheaper altern

If I had to guess, it is similar to why people spend small fortunes on diamonds - despite being a horrible financial decision and having superior/cheaper alternatives, a series of a societal pressures (mainly advertising, at this point) has resulted in people making a behavioral decision that is far less than optimal based on any reasonable metric. Also, people are bad at changing habits. Really bad. And as ridiculous as it is, a huge portion of the US thinks bidets are for the French, gays, and women... all of which are thought of as pejoratives. I am not as familiar with the ignorances and stupidities of other countries.