I mean, cash is also expensive in its own way. It has to be handled and insured, coins may need to be rolled before being taken to the bank, a register is a mechanical device to power and maintain, petty theft by employees is a concern.
It's not really that hard to see why a business charging $5-20 per transaction from people who all have phones and credit cards anyway might choose not to accept cash.
It's not really that hard to see why a business charging $5-20 per transaction from people who all have phones and credit cards anyway might choose not to accept cash.