Not necessarily ridiculous, if you need hard copies of most of the faxes anyway. Though my choice would probably be to set up a computer with fax-modem connected to either a VoIP or regular line.
As far as Japan, their embrace and adoption of technology is weird and uneven. I was there in 1995, and rotary phones were still relatively common, some places outside Tokyo also required an operator to dial the States.
Their phone network was 10-15 years behind the US in the 1990s.