The casino cage worker is very much like a bank teller, exchanging cash for chips or tokens and back again. While bills of any size can be exchanged for chips at tables, it's possible for a player to make their exchange of foreign currency or personal or certified check.
Casino cage workers also arrange for chips based on lines of credit opened for players. The workers can process credit applications and handle the routines for doing credit checks.
After the playing is over, the cage worker will also turn the players' chips back into currency, something the dealers at the tables cannot do.
The cage workers can also give players their money in the form of checks or money orders. Again, depending on the size of the establishment, these workers can also be handling bank wire transfers with nearly any financial institution in the world.
Like most of the casino floor jobs, the casino cage worker does a lot of customer service. While performing their regular jobs of exchanging funds, they're also giving people directions around the building (or city), fielding questions about policy or directing guests to people who can help them specifically.
Because people lose money at casinos more often than they win, cage workers can expect to be the recipients of some amount of abuse from losing players. The workers will have to be able to differentiate between simple grumbling and the precursors of real problem behavior.
