Electronic payment isn't working out for some Singapore hawkers.
"Apart from inconsistencies, other hawkers that CNA spoke to also cited the need for immediate cash and their lack of understanding of technology as reasons for restricting transactions to cash.
[...]
During busy hours, it is also more efficient to collect cash rather than wait and confirm that an e-payment was successful, the worker said."
https://www.channelnewsasia.com/singapore/cash-only-hawkers-tech-scams-digital-payments-3337131