This happens not only when objects are on top of other objects like buildings but just on plain ground.
Example run of attached mission with 2 points of view
Player 1 (server, spawns Suitcase): http://www.youtube.com/watch?v=RdDGgKD6Lq8
Player 2 (client, spawns Fuel can): http://www.youtube.com/watch?v=bLaN6J3MxrA
as you can see non-local objects fly all over the place.
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Client view of server-owned crate: http://www.youtube.com/watch?v=8ZDteVo4ZlU
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Related: http://www.youtube.com/watch?v=aN85jUTfSJQ
Related №2: http://www.youtube.com/watch?v=xW5gMhdWyag
Non-local vehicles sometimes under unknown circumstances start to fly all over the place similar to how suitcase and fuelcan do in the repro for this ticket.