Why do bee escapes work to clear honey supers?

[twb]

Now that I have an obs hive I see that bees stay on their frame filled with honey even throughout the night.  The warmer the night the more bees on the frame.  That got me wondering why bees would vacate their honey stores when a triangle bee escape(or whatever type) is used.  Are they seeking a stronger queen scent after her smell gets blocked by the excluder?  Thoughts?

[Michael Bush]

They always want to move down during the night and it lets them.  Other than that, it works just like a minnow trap.