This is not an uncommon phenomena. ORD, DFW and other non Soutwest served trunk based hub cities have or had very high prices in and out of them. Price DFW vs. SAT or AUS from most cities. That's how Hidden City tickets first got developed.
Not long ago one way JFK-LAX was $1,150. JFK-ONT (or LAS) connecting through LAX was about $150.