I did a project to translate data framed in the ASCII field/record separator characters and it was gloriously easy. All the ugly escaping considerations with comma-delimited data went away and it became much easier.
I suppose you could document that it's unsupported, and just drop or reject such values, but then the system couldn't be used to handle test data for such systems, for example.
Otherwise you need to have some sort of escape mechanism, exactly like quoting strings in CSV. In fact, there's an ASCII code "ESC" for entirely that purpose. :)
The problem is that those characters are non-printable, which means if you're just dumping the file out somewhere, you can't see them.