The problem with doing laundry at home is that it is a single threaded process, that only moves as fast as the dryer dries. I had four loads to complete this evening: work clothes, sweats and tee-shirts, whites, and towels. I started when I got home at 5:00. It is now 9:25 and the THIRD load (the whites) is still in the dryer. Luckily the towels can stay in the dryer until tomorrow after they finish. At least the rest of my life (such as it is) goes on in the background at home. I can eat dinner, watch Tivo, use the computer, et cetera.
Laundromats, on the other hand let you multi-thread your laundry. Use as many washers or dryers simultaneously as you want/need. Of course there your life is single threaded as you are stuck in a hot, smelly place that you’d rather not visit if you had a choice
At home you get to use the quarters for something else too.