... Nobody gives a shit who's living next door in large cities. You would probably only notice that someone in your apartment megacomplex died because after a few months in Summer it starts to smell funny.
Nonsense. Condo homeowners' associations work to keep the property values up – by law – so they order maintenance & repairs, and hire & track services such as janitorial, gardening, and so on. Many in the community take their turn on the HOA Board every few years, depending. This keeps things stable for the community.
Now imagine one owner starts renting out their unit to vacationing groups of frat boys every weekend. I might not know my neighbors' hobby (actually I do), but the HOA Board will be hearing from me, and that same neighbor will be hearing from the HOA Board, which functions as an intermediary.
Short-term rentals are against zoning laws, HOA rules & regs, and the very concept of having a home in a "community".