Shmos 25 (6) lists amongst the materials needed for the mishkan "oil for lighting, spices for the anointing oil and for the incense" which seem to be consumables and not for the building of the mishkan. The Daas Zekainim points out the incongruity especially as the wheat for the Shewbread the lambs for the daily sacrifice and the wood for the altar are not mentioned.
He and the Chizkuni answer that it is customary to perfume the palace and light lights (even though He does not need the light) before the King comes to palace. In the mishkan too, G-d could not, so to speak, dwell there until there was perfume and light.
Therefore these materials were essential to the construction of the mishkan. Without them G-d could not have, so to speak, dwelt there.
I clearly do not understand the answer sufficiently because the question still seems to me to be better than the answer.
Can someone please explain or quote another answer?