I wonder whether the number of people who still want to pay cash would be small enough, that park rangers don't end up with a lot of cash to get rid of, nor nee

I wonder whether the number of people who still want to pay cash would be small enough, that park rangers don't end up with a lot of cash to get rid of, nor need costly cash-handling procedures, nor have a safety problem. For example, if nearby rural businesses prefer cash, such as due to low-9s uptime of electronic connectivity, maybe the rangers could use a petty cash fund for official purposes. Or some park service locations could offer a service of "cash back" to visitors with debit/credit cards, when cash on hand permits. This sounds odd and off-mission, but this would be the US gov't symbolically showing that US currency works in every corner of the nation, even when getting back to nature, where electronics can be less reliable.