I like your thought process. But where does the gravity originate on this rotating sphere (earth) which is moving around the sun all the while shooting through the solar system at outrageous velocities? When we were on a merry-go-round you went fast enough in a circle you would fly off.
Most scientists will say that space is a
vacuum.
However, if this magical gravity (which can distinguish the weights of the oceans and birds of the air) exist then you should be able to replicate, in an experiement, the spherical earth where water sticks to it's rotating surface while vacuum and pressure exist next to each other without a barrier.