CPAN modules are free. But commercial replacements for XML::Edifact start at $100k not including the required consultant to implement it. So it was cheaper for them to pay me for consulting and maintenance.

The Perl Module is bug free for ages. But the UN/EDIFACT standard improves twice a year, while XML::Edifact comes still bundled with a 1996 version of the standard. Its easy to replace/update it, but those companies always have custom code list extensions, and merging them is basically my maintenance.