I forget what video I watched that explained this, but it essentially said:
“The audio mixing is correct. It is mixed for full surround sound, like those you see in home theaters (probably the very expensive setups!) and actual theaters. There is no reason to have dual-mixed sound, one for those with stereo speakers and one for the surround sound setups, so they don’t.”
It does look like there is a much bigger cage in the background. Either way, thank you for the very in-depth explanation for hamsters. I literally had no idea (never wanted one, but they are very cute), so now I know what to look for if I ever meet someone who has one! Cheers!