You've compiled a vast collection of supposition, just to prove an arbitrary point of your own. And you insist that we support it. So I don't know where this discussion is going to go ... however.
The Earth loses tons of its atmosphere, and has been, since it formed. However, like other planets that allow life to evolve, it has a supply that takes billions of years to deplete by this method: http://en.wikipedia.org/wiki/Atmospheric_escape#Dominant_atmospheric_escape_and_loss_processes_on_Earth
There's no diatomic hydrogen in the Earth's atmosphere, because its reactive enough to form compounds. All the hydrogen you've found lying around came from decomposition of Earths water, supplies of which are vast on the scale of "floating away" depletion that you describe. Probably much of the lost hydrogen re-enters the hydrological cycle, oxizied by some atmospheric process. The planets Mercury and Venus lost all their lighter elements because they have no cyclical processing and the solar wind was able to ionize and strip it away. But even in those cases, it didn't simply flow away.
Earth's atmosphere is not stratified by component density. You assume the hydrogen and helium are floating like corks to the top of the atmosphere and flying away. That's simply not the case. If it were, then denser gases should be accumulating at our feet. Even without the wind, a "solution" of gases doesn't stratify in that way, any more than a salt water solution ends up with a "pile" of Na+ ions on the bottom, under a layer of CL- ions with the water on top, the mixture is in constant molecular motion to keep it mixed.