In fact, credit cards can serve as your life line during emergency which may require that you make instant payment even though you don't have money in your bank account. (myfinancekits.com)
That means that if they knew they didn't have the money in their bank account to pay for the purchase, then they shouldn't buy it with a credit card either. (cheapscholar.org)
Other than emergencies, credit cards should only be used when you already have money in your bank account to cover the charges. (greenpath.com)