It’s not terribly hard to get into that position, if you spend 40 years of your time and treasure on something with resale value instead of on food and experiences.
You can do something similar if you buy a house and keep buying any neighboring house that comes up for sale (and renting them out, perhaps).
You can do something similar if you buy a house and keep buying any neighboring house that comes up for sale (and renting them out, perhaps).