It’s moving at the same rate as the earth’s rotation.
Aren’t we all?
“It’s moving at the same rate as the earth’s rotation.”
Of course. But what is the point of your post?
If you're shooting along an east-west line (line of latitude). If you're shooting along a north-south line (longitude), the velocity east-west velocity of the point closer to the equator is going to be greater than that of the point farther from the equator.
This effect is more pronounced at higher latitudes (that is, more northerly locations, in the CONUS).
Only if you’re shooting exactly east or west, any component of north or south and you’ll have difference of conferences that you have to account for, think about it.