So, the orbs hijacked the plane into another dimension. Maybe they eat humans there.
No. They don't eat them like we would eat a pizza.
The 'aliens' are spiritual/supernatural and not exactly 'solid matter'. They 'jump into' a human host and then can experience all the emotions/feelings/pleasure/pain/etc that we humans have. Without being in a material host,solidly on the physical plane, they cannot experience any of that.
Among the spiritual/supernatural/etc 'beings' those human experiences are cherished and difficult to obtain.
These 'beings' are like human beings in one particular way. They desire and value the most the things they do not have.
That 'channel' being common to humans and these beings is likely the manner in which they can penetrate the human psyche and and the path to taking command of the body.
They took the plane, ate the Chinese and, after a few hours, became hungary so got mad and then dropped the plane in the ocean.
Makes sense/s