I don't consider myself a water hoarder (I picked up 2 cases last trip instead of my usual 1), but I look at it this way: Houston just went through a fairly serious need for water after the water main break. Couple that with Coronavirus and the upcoming hurricane season (which you should stock up on water for anyway), and you have a lot of nervous people out there. Would you rather get some water now, while there only a handful of confirmed cases and you yourself are well, or do it later, when confirmed (and unconfirmed) cases are likely much higher and there's a chance you aren't well, or are self-quarantining?

(Because you know how that's going to go. "OK. I've been told to self-quarantine. Which I'll do right away. Just as soon as I stop off here, because I really need X. And here, because I've just got to have Y. Then I'll go home.")

Personally I'd rather go to a store and get stuff now, while there is a higher chance of being surrounded by people who aren't sick. I don't see anything wrong with preparing early as I consider this the calm before a "potential" shitstorm. But I think it's smart to prepare calmly and reasonably and without unnecessary hoarding.