My family's been in the cemetery industry for about 60 years, and your last observation is rather interesting from my perspective. You're absolutely right that cemeteries aren't for the dead. They're for the living, some people do take a degree of comfort--maybe even satisfaction--in knowing where they'll be buried. I've actually seen people bring a blanket out and sit for hours at their future gravesite, odd though that may have seemed to my younger self.
In my anecdotal experience, most modern/currently operating cemeteries aren't really situated in the best real estate. But most landscaping maintenance and beautification practices do tend to make them appear more inviting/relaxing/beautiful than just the land itself would seem to be on its own. In that sense, they're not all that different from parks; the name "memorial park" (cemeteries with bronze or sometimes stone markers flush to the ground) and the ideas behind the philosophy pretty explicitly evoke that image.
Older, historical cemeteries are a different matter altogether. As another commenter pointed out, some of them were originally located outside the urban core but still close enough for relatively easy access to transportation. Church cemeteries were often located immediately outside the church. Some were never really envisioned to amount to anything, but expanded slowly over time. The same passage of time turned their locations into valuable, prime real estate. And the same landscaping and greenery that most cemeteries try to cultivate, along with the sheer weight of history on their grounds, can turn them into wonderful places for the community to visit. Many of the monuments and private mausoleums are stunning pieces of architecture and workmanship, and the dark Quincy granite that you'll often find is instantly recognizable. Even more so than their natural beauty, these places tell a part of our history, good and bad. Not every cemetery was preserved like that, of course; others are forgotten entirely and re-discovered during construction projects. Or they can be damaged by natural disasters, such as when a thousand caskets floated away after Hurricane Katrina and had to be tracked down and reinterred.
Sometimes, that land is too appealing or valuable, which can lead to cemeteries being moved to another location in their entirely. It's such a royal pain in the ass, though, it's very rare nowadays unless there's no alternative such as with major infrastructure projects and the like, with many states having laws that protect cemeteries from arbitrary eminent domain and redevelopment, and requiring court orders for each individual grave, efforts to track down next of kin, etc. My grandfather's company was hired to help move a cemetery for a University of Pittsburgh stadium back in the late 50s or early 60s, if I recall correctly. Years earlier, it was much more common to move cemeteries and reinter the remains as cities grew. Sometimes happening more than once, which can give genealogists fits at times.
As for the environmental impact, you can look into alkaline hydrolysis as a cremation alternative, at least in the 14 states it's currently legal in.[0] It's much more environmentally friendly (no mercury pollution, for example), save for the wastewater it produces (around 300 gallons per body).
0. https://www.wired.co.uk/article/alkaline-hydrolysis-biocrema...