I can see why some employers do it. They want to avoid any feelings, confrontation, feedback, or they want to wait for a better candidate while keeping a decent one as an option. Some of them are just pure lazy and unprofessional.
When I was in college, I interviewed for an intern position at Cisco. I had 3 rounds of interviews. Then nothing for weeks/months. I only found out I didn't get a job when one of my classmates changed her Linkedin profile that shows she got it. I was professional, sending thank you letters to everyone after the interviews and addressing everyone as Mr./Ms. Cisco was the unprofessional party. It was a total waste of my time waiting, anticipating. I swore I would never work for them in my life.
Being ghosted affects the livelihood of the candidate much more so than the employer. It's a good law.