In one of the apartments I lived in while I was in graduate school, my upstairs neighbor had a job where she worked really late into the early a.m. hours. I guess when she got home, she wasn't ready to go to bed right away, so she would do household chores, like vacuuming. It would wake me up, of course, living below her. And if she used the garbage disposal first, I would jolt up from a deep sleep state until I figured out she was home and doing chores again. If it happened recently, like for the student who made these comments, then it is something that would be uppermost on one's mind, IMO. Losing sleep regularly like that is a real problem.
When I moved, I made sure I had an upstairs apartment.