you don't. and now there are lots of stablecoins (back when there was only tether, very sketchy), so people can send pretty safe dollars. 1/
there's no reason why a band can't put an ETH address as a payment destination. depending what network is used, transfers can be nearly free. (base ETH is most expensive. for the first time in a couple of years, i recently transacted there, a token transfer cost ~70¢.) 2/
if you are starting up some kind of group informally, you can avoid incorporation and bank accounts and have a crypto wallet that requires authorizations from three-out-of-five or whatever, off the shelf. people can donate with some assurance the guy with the envelope of cash doesn't walk away. 3/