I work in international freight and this is still a thing. Most customs brokers are email now, but some still require documents be faxed. So our system takes the PDF that it auto generates for every shipment and faxes it to the number on file. From time to time those same brokers will email us a copy of the PDF we faxed them to have something corrected. So they are getting the fax in their email rather than having us just email the thing directly. It makes zero sense, like I understand keeping the fax capability for legacy customers and as a backup, but your primary should be email if it's all going there anyway.