From Plutarch’s life of Themistocles, the Athenian politician and general who led the Greeks in their successful war against Persia. Themistocles has just been exiled from Athens:
A great part of his estate was privately conveyed away by his friends, and sent after him by sea into Asia; besides which, there was discovered and confiscated to the value of four-score talents, as Theophrastus writes; Theopompus says an hundred; though Themistocles was never worth three talents before he was concerned in public affairs.
A Greek talent is a little less than 60 pounds (enough water to fill a particular amount of space). Or the amount of silver necessary to pay a trireme crew for a month. Approximately 6,000 drachmas. Lots of silver, maybe 600,000. A lot of money, now or then.
But it doesn’t end there. In his exile, Themistocles presents himself to the king of Persia (some say Xerxes, some say Xerxes successor, who Plutarch does not appear to name. And receives 200 talents for offering his services to the Persians.
It seems “public service” has always paid.