Blessing on the Seven-Day Lulav

Peace to my dear Rabbi Michi.
We wave the lulav for 7 days and say blessings for it, but basically, according to the Torah, one should only wave it one day in the country, and that is just a reminder of the Temple. This was not determined by the Sanhedrin. Therefore, there is no point in saying blessings because of hearing the words of the sages, so why do we say blessings?