Can't really answer your question, but on the kernel mailing list, There has been some discussion of whether these attributes should be exposed from mounted fat partitions: The fat fs maintainer has a patch, and is wondering what to do with it. (The patch exposes the fat attributes as extended attributes)
See the thread titled "[RFC] ioctl vs xattr for the filesystem specific attributes".
yup that would help (to expose FAT attributes) my only remark is that we need to open the file in order to get its attributes I wonder if there would be an impact performance wise