Going to bed is just setting your body and brain down in a safe place, so you can use them later.

Just?

Is your your brain setting your body down to bed? Your bed setting your body down to sleep? Do you have free will, or are we little automatons in a closed, predictable system?

Why does resting my brain take my brain to another world without my body?

...just... 🙄

You don't also escape into the unseen, transform into a beautiful butterfly, and frolic through the planes?

It's more shutting down so your cells can repair all the drinking and fast food you ate.

Your bed is just a shelf you store your body on when not in use.