a figure of speech by which a part is put for the whole (as fifty sail for fifty ships), the whole for a part (as society for high society), the species for the genus (as cutthroat for assassin), the genus for the species (as a creature for a man), or the name of the material for the thing made (as boards for stage)
a young culture so willingly bombarded with messages equating what one consumes with who one is that brand loyalty is now an acceptable synecdoche of identity, of character
this is a great quote, incidentally