This is a political design. The use or lack of colour helps extenuate the point the creator wants to create. The use of flowers, as a severe contrast to violence and war, also shows the message of peace, not war. Powerful visuals in a simple way.
10+ Of The Funniest Reactions To Super Sad Pope Meeting The Trumps
This photo demonstrates how pollution is impacting and destroying the earth. It shows that we as humans are oblivious to this and aren't trying to take action against reducing our ecological footprint.