No, subbase and base mostly use inorganic binder to stabilize materials, which are rough and have large surface cracks, so the curing agent can't seal the holes on the surface and water. The concrete surface is smooth and dense, and the curing agent can seal the surface well.

This truth is like painting a wall, painting a wall with thick mortar. Generally, the wall paint is not brushed directly, but a layer of putty is scraped, and then the wall paint is brushed after the surface is smooth and dense.