It's sort of a virus, e.g. in Germany. One of the first things
the average
user does after a distribution upgrade is to edit /etc/sysconfig/i18n and
change from UTF-8 to @euro or ISO 8859-1. The reason is that the effects
of this change are not understood. It just "seems to work" with old
Latin-1 file names, file contents and non-Unicode-aware applications.
The file system is still UTF-8, its just the user is filling it with
garbage now. The update is a pain but there are some handy scripts for
doing things like turning a subtree from 8859-15 to utf-8