Why get into an argument over this ? Just change some dollars in the airport or withdraw some shekels from the ATM ! Would you fly into JFK and try to pay a cab driver in Euros or another currency?

The shekel has been steady against the dollar for the last 15 years and Israelis do not generally invest in foreign currency based securities any more. I sincerely doubt that any cab driver is interested in "speculating" with your $15 !