apushatayid:
With the emphasis on kovod shabbos. In no way does this imply that this same man should or must wear one during the week. Nor does it imply that the hat must be made of black felt. It could have been yellow straw.
If you’d like to say he only considered it the right thing to do for Shabbos, I can’t argue, since I don’t know. One can ask Rabbi Shachter or Rabbi Meiselman.