Unfortunately people are being stupid at the moment and trying to hoard bottled water. I've heard that some stores are now restricting how much people can buy at a time. They hadn't anticipated how foolish some people would be, so they hadn't thought to do it sooner.
I just organised a delivery of bottled spring water (so not using municipal water) for my 74 yr old mother. Hoping to avoid her having to go out and collect water if at all possible.
Due to a natural disaster (fire) my town was without water from January to March of last year. We had to rely on donated water and water trucked in from outside. It was not fun. Water is heavy to carry and bulky. You need less than you think to survive but the entire process of going to fetch water from the truck, manage the bottles, carry the bottles - it is exhausting and time consuming. And by the time the water has gone through the pump to get in the tank, sat in the tank, and pumped out again it tastes pretty funky. So I do not blame people in the slightest for stockpiling some decent drinking water.
I still have bottles of water stored for when the water goes dirty (as it does after every rainfall. It will be like this for several years until the vegetation on the mountain recovers enough to hold the soil). In fact this week we had no drinking water again all week. Rained Sunday, Monday and Thursday so the water is brown. The e-coli count goes through the roof as well. (It also runs out practically every Sunday afternoon, but that is another story entirely).
Dry taps? Cape Town welcome to a daily reality for many people.