[pkroll]

A rooftop of a residential high rise isn't a place filled with machinery, it's patio space. The whole top floor is either one or two apartments, has 14' high ceilings, and the very richest live there. They're not gonna want Amazon to land a drone in the middle of their party, nor have anyone come up to say Hi and pick up a package.

[Guest98123]

That's simply not true. Take a look at Google maps and you'll realize the vast majority of residential high rises are actually filled with equipment, huge fans, loud air-conditioners and empty space. Most have terraces and pools on lower floors, and most penthouses don't have rooftop access.

For example, look at the below image of high rise condos in Chicago. They're all filled with heavy equipment. They're not filled with the super rich having extravagant cocktail parties.

http://i.imgur.com/QC8rakm.jpg

[arantius]

In my experience in NYC, most buildings have some mechanical and some recreational space somewhere on their roofs and/or balconies. Sometimes this is private recreational space, sometimes shared, sometimes a little of both.