3,000 pounds? Even with the reduced gravity the site is heavily footprinted by those big lunar boots. If you recall - or watch - the old taped footage you will notice at least once the lunar hiker kicked up quite a bit of dust just hopping around.
Newton's law applies. In a vacuum a proportionally higher rocket thrust is required since the "atmosphere" it is pushing against has almost zero mass even with our gravitational level on earth - let alone under the lesser pull of the moon.
But I am sure it is all there; those primitive 1960s technology still photos just need that modern digital enhancement.
On the landing sequence, you could see all the dust radiating away from the lander as it touched down. The problem is more that the gray dust/regolith and the gray subsurface rock look just about identical. And that the dust/regolith depth is just only about an inch inch-and-a-half in most places. Also, the average albedo of the Moon is about that of fresh black asphalt. It just looks gray/white due to overexposure under full sun. (If you could magically transport a chunk of terrestrial parking lot lit by noonday sun to nighttime, it would look just as brilliant as the Moon does.) So the "dust crater" probably is there under the lander with scrubbed subsurface bedrock, it's just not that visible because it's only an inch deep, and it's a matter of trying to see dark black dust against dark black rock under the shadow of the lander.
Also, out from underneath the lander and the rocket wash, the expelled dust went from a fluid dynamic type of propogation to a purely ballistic one as the miniscule pressure from the exhaust gasses fell away quickly and the dust particles were on a purely ballistic vaccuum trajectory so it would not spread in the way your brain which has been trained from birth to understand the dynamics of living in atmosphere.
Also, your understanding of Newton's law is well...
A rocket's thrust pushes against nothing but it's exhaust, it's momentum transfer from expelled mass. Whether it's in atmosphere or vaccuum. If anything, operating in atmosphere requires more thrust because you're overcoming the drag on the entire rocket, and operating in atmosphere tends to reduce your specific impulse because it clamps down on the expulsion velocity of the exhaust gasses.
Here's an analogy, If you sit on a wheeled office chair and push yourself across the room by throwing heavy books, do the books push you by pushing on the air that then somehow pushes you back? Of course not, you "push" by throwing the book, and it's one single interaction that propels you the other way. One of those books behaves exactly the same as one molocule of exhaust gas from a rocket.
It's okay though, I had to explain this to my high-school physics teacher as well. He wasn't a science teacher by trade, just new, and got assigned that class by default and only had the textbook to work from.
