On the ISS, the Cupola is used to observe operations:
The International Space Station Cupola was first conceived in 1987 by Space Station Man-Systems Architectural Control Manager Gary Kitmacher as a workstation for operating the station’s Canadarm2 robotic arm, maneuvering vehicles outside the station, and observing and supporting spacewalks. He likened the use as similar to that of the Shuttle Orbiter Aft Flight Deck.
I wouldn't dismiss giving the astronauts a window to look out of as unimportant. Several astronauts I've heard speak, said the most profound change they went through was in the way they look at Earth: they came to understand how fragile Earth's society and ecosystem is, and how rapidly the ecosystem is changing for the worse.
Source for the last paragraph: a 3-hour talk by astronaut André Kuipers, almost half of it was spent sharing his observations of Earth and the changes he's seen between 2 missions ~10 years apart. Some changes are obvious to the naked eye, others can be easily seen if you have 2 photos of the same region taken at different times.
Orbiting Earth 2593 times, what I really came to appreciate was the commonality of the human experience. From orbit you see the repeated patterns of human settlement and civilisation, and inevitably start to sense that each of us inherently wants the same things out of life - joy, grace, time and stability to think, better opportunities for our children, laughter, someone to love. The precept of 'Us' and 'Them' is one that is taught; it's not the fundamental reality. Seeing the whole world as 1 place every 92 minutes drove that home within me, forever.
You develop an instant global consciousness, a people orientation, an intense dissatisfaction with the state of the world, and a compulsion to do something about it. From out there on the moon, international politics look so petty. You want to grab a politician by the scruff of the neck and drag him a quarter of a million miles out and say, "Look at that, you son of a bitch."
The view of Earth is the biggest thing, and it is probably the thing that has the biggest impact on you, so it is quite natural that is the thing you will miss the most
From up here I can see humanity’s footprint, including forest fires, air pollution and erosion
Example photo taken from the ISS of the Amazon rainforest. Dark green = rainforest. Lighter colors = forest chopped down to be replaced with agriculture.