Freehand was Macromedia's vector graphics app. Adobe bought Macromedia in 2005 I think so ditched Freehand so that Illustrator would take its place. I don't see why a company would specify the use of such an old piece of software unless they still have it installed on an old machine. Often the person writing the job spec/advert might not have design experience and might copy the spec from an older advertisement rather than revise it to be more up to date. I do often see companies specify random software on job adverts i.e Flash AS4.. (which doesnt exist).
Maybe they have a large back catalogue of files produced in freehand which cannot be transferred to illustrator for whatever reason (I cant even remember the file extensions freehand used let alone if theyre compatible with illy)?
*Irrelevant Fact Alert*
I was taught on the Macromedia software when I first started college, I think I've actually got the MX suite somewhere at my parents.. The only thing I can remember about it is that I preferred learning Director over Flash and that the gradients in freehand seemed far more logical than the gradient mesh tool in illy.