Why do so many people HATE the New England Patriots -- the greatest dynasty in the history of pro sports?
That's the question we posed to Rob Gronkowski's smokin' hot girlfriend, Camille Kostek -- and her answer was simple ... JEALOUSY!
"They hate us 'cause they ain't us," the former Pats cheerleader told us at LAX.
Kostek -- who's also a Sports Illustrated Swimsuit Edition model -- just got off the plane from Kansas City where she battled freezing temperatures to support the future Hall of Famer .