Composer fields

[eschiss1]

why does everyone seem to put composers lastname-first in the composer (and other) fields in iTunes-tagging, out of curiosity- recent and not so recent versions of iTunes (though admittedly, less recent versions, not so much) support sortability up-the(etc.) so one can have such and so for display, and such and so for sort- or can the sort fields not be sent in files, just the displayed fields? (That is interesting information and did not know that... still, always set them myself on receipt of course...) I realize iTunes is not the software most people use, is part of the answer, true... (do other programs not also use the sortfields? Hrm...)
Curiosity, rather than complaint or rhetorical question, and a response therefore requested?... thanks