This might have something to do with the WHY:
Revelations: 4:8 and following:
8 And the four beasts had each of them six wings about him; and they were full of eyes within: and they rest not day and night, saying, Holy, holy, holy, Lord God Almighty, which was, and is, and is to come.
9 And when those beasts give glory and honor and thanks to him that sat on the throne, who liveth for ever and ever,
10 the four and twenty elders fall down before him that sat on the throne, and worship him that liveth for ever and ever, and cast their crowns before the throne,
Good enough for the four and twenty elders…good enough for me…and I suspect for the rest of us. It's the Tradition.
Recall that this is done at the entry of the Holy Gospel which is set upon the throne. There is then a parallel in this and the Heavenly worship.