There is obviously some truth in the old adage "out of sight, out of mind." Humans are a visual species with large areas of our brain dedicated to processive visual stimuli. Most of our knowledge concerning our surroundings is acquired through our eyes.
We tend to deem matters that can't be clearly seen as low priority, and for a great many people, if a concern can't be observed directly or unambiguously, it apparently does not exist in their mind. Herein lies a problem as it relates to addressing some of our most serious environmental issues, because they first must be acknowledged.