The Atlantis these days uses more coins making change for restaurant patrons than it does for the 100 or so coin-operated slots scattered throughout the casino floor.Much like the Betamax and film cameras, coin-operated slots are relegated to Nevada's past. Big properties in northern Nevada still have small percentages of the machines on their casino floors, and older, smaller casinos use them much more frequently, but by and large coin slots have faded from existence.And with them went a whole way of doing business for casino operators. Gone are entire fleets of casino workers employed as key people, change persons …