A human shadow, or just a shadow?
This would explain the title as these are seen everyday
I have a mouth but, I don't eat with it
As long as the object has a mouth then so does the shadow, but a shadow can't eat
My body doesn't support me, but I eat with that
Not sure about the second bit, but a shadows body doesn't support itself, maybe a shadow eats the light?
I have a comfy bed but never sleep in it
whether it is night or day
A human has a bed but their shadow can't sleep in it
I love to run, but can't slow down to a jog,
but I can a raging bull
Don't know about running, but a raging bull has a shadow?
I can be shorter than a dwarf
e.g. a fly's shadow
Or taller than a skyscraper
e.g. Mount Everest's shadow
You better watch out
the hope for survival
just turned to your worst nightmare
Not sure, but most nightmares consist of shadows and darkness