Indeed, in general we are not aware of how much we dream, because we don't remember. I should have specified better. Weed and alcohol specifically suppress REM

Indeed, in general we are not aware of how much we dream, because we don't remember. I should have specified better. Weed and alcohol specifically suppress REM sleep, where most of dreaming happens. Suddenly stopping weed or alcohol leads to a REM rebound, and people experience very vivid dreams. This association suggests they were actually not dreaming much before.