Suppose your water was turned off. Maybe because you're working on one of the bathrooms and there's a leak but your expertise has a terrible migraine so you can't finish it so you have to turn your water off so that the pipe doesn't pop and destroy your already destroyed bathroom. It could happen. Trust me.
So how do you brush your teeth? Go to the bathroom? Make dinner? Shower?
In Utah, we were good enough friends with our neighbors that we could have justed pop over there. Here my parents are one neighborhood over and my sister a couple miles away. We have a couple gallons of drinking water, and lots of options, but it definitely brought home the need for water storage as part of one's emergency preparedness.
So, um, yeah. Now would be a good time to figure out where you would shower if your water had to be turned off.