Originally Posted by
futuramadramallama
I tried to follow your link for NYC-LAS but the itinerary isn't available; could you describe the date range or routing you saw?
Google is doing that because the flight combination is no longer available. Alaska had some super cheap fares one way from JFK to LAS which made this possible. The cheapest flights now are $208 roundtrip on Delta and jetBlue in May.
See the dip in the chart below on Google Flights.
