I am not 100% sure what you are asking, but the shortage of cash this month in Greece is due to the closing of banks and prevention of most banks transaction.
When, middle/end of June discussions looked like there would be no agreement, and that a Grexit would probably be the only way out, people went to withdraw their money from their bank account. As a possible Grexit would imply a change of currency, combined with a rapid devaluation. That would make the value of banks accounts quite uncertain. People prefered to withdraw to be on the safe side.
However, to prevent a total collapse of their banking system, the government had to try to prevent the huge amount of money getting out of the banks. Their first measure was to limit the amound of cash that can be withdrawn: 60€/day for each inhabitant. The inhabitants being skeptic, tend to accumulate that money at home (not all flee outside).
However that doesn't prevent bank transfers towards foreign countries (probably favoured by high/middle class members). So they also stopped that. As a consequence, cash is the only mean of payment in Greece, even for salaries. Which amplify the need for the Greeks to collect cash with themselves to pay employee's income, food, and all kind of services that are needed and that can't be paid for with alternative means (credit cards, check, transfers, etc.).