I have in fact when I was a student. Granted they were only my clothes and I tried not to dirty them but also used a laundromat in most instances. Sometimes would ask a friend for access to a machine.
It is both back-breaking and time-intensive especially if you are trying to get clean laundry not just "smells of detergent" laundry. And especially if there's someone who does manual labour in the household - getting heavy stains out effectively doubles your workload. There are many people who cannot just "try not to dirty" their clothes.
I am not trying to downplay your experience. But student poverty and poverty in the adult world without all the cushioning of a campus are very different kettles of fish.
https://en.wikipedia.org/wiki/Amish
There is a reason
See also Ted talk about best invention ever by factfulness guy