Why don't we see huge clouds of dust in the low gravity?

Because dust clouds depend on air. If an atmosphere is dense enough, it can hold small particles suspended against gravity for a short time. Particles suspended in the air like that are called aerosols. Smoke and dust are both solid aerosols. Smoke can be carried for a long distance in earth's atmosphere. Dust particles are heavier than smoke particles and so they settle out faster. Both show us the movement of the air that's carrying them; we see billows and curls in the clouds of smoke and dust.

None of that would happen on the moon because there's nothing to keep the dust particles suspended. Galileo showed us that gravity accelerates all objects the same regardless of any difference in mass. On earth the air prevents some objects from falling as fast as others, especially very, very small objects like dust particles. But on the moon only gravity affects them, so dust will fall immediately to the lunar surface.