There is very little business case for support of this protocol now, but the dropping of support for older protocols is an irritation for me and anyone else who isn't totally in favor of our throwaway society.
Anything new I have will not be FAT16, but I still have floppy disc drives with old information and data stored on them. A USB floppy drive keeps them accessible on relatively current machinery. Sure, I could take a few days and copy them off onto some new media. This is just one example, there are many others where the obsolete hardware found in closets, surplus stores and waste bins still has value to someone.
While it isn't FAT related, a similar example is the ink jet printer I use at home, which was a fairly high end small business all in one model when new. It still functions perfectly, with multiple paper trays, duplex printing, multi-sheet scanning etc. In the Windows environment the currently available drivers only support relatively simple printing tasks. Scanning is virtually impossible. Under Linux I can get better support, but nothing like the features that came with the drivers that worked under Windows XP.