Baal Habooze – I am talking through my hat here, but this weeks Parsha discusses parts of the daily avodah in the bais hamikdash – it could be that besides for the kiyor being part of the binyan habayis, part of the tzurah for the avodah was to have a kiyar there. (I have heard this sort of vort b’nogea the hadlokas hamenorah and the lechem haponim, in different variations.)
