> Where are you from that sharing a home with strangers is such a strange concept?
Sweden.
When I went to university, I had a student apartment. It was cheap and tiny, 18m^2. There was a slightly cheaper student housing option where you would share a living room and a kitchen with other people, but in those everyone has their own private bedroom and bathroom with their own front door. Some of my friends rented regular, small apartments in the city. Some shared apartments, but always with existing friends, people they'd known for a while and knew they'd get along with.
As you exit university, you lose your student housing, but if you have a job you can usually afford a small apartment, a studio or a 1BR. The amount of people sharing an apartment with others at this age is even lower.
Eventually, most people get into a relationship, and move into a larger home as needed, and this is where the attitudes between the US and Sweden are the most similar, if you have a family and kids, most people get a house of their own.
One difference between the US and Sweden though is that there is strong political pressure for construction companies to build small apartments. In the US there's political pressure to build low-income housing and accessible housing, but for some reason no pressure for making sure everyone gets their own apartment?