I agree with most commenters here that cash is useful and that cashless is a step in the wrong direction. I did want to point out, though, that this differs a lot from what at least some commenters on other forums are saying about the ban. All the top voted comments on Reddit about this are against it: https://www.reddit.com/r/washdc/comments/16wacjy/dcs_ban_on_...

I find the difference in opinion between the HN crowd and Reddit kind of interesting. Part of it is probably because that is a local to DC subreddit, but I also believe they're not really considering the privacy / civic resilience angle.

From my perspective, having lived through a near total power outage in Texas for a week in February 2021, having some cash, food, and drinking water on hand is just basic common sense these days. Some local grocers were letting people take groceries without paying, anecdotally, but I don't think that was everywhere or even corporate policy. You also don't want to rely on that to feed your family or pay for basic goods in an emergency. At one point, even the cell network was starting to go down in my area because the generators powering the cell towers were running out of fuel.