Earlier in the film, before the two switch, Cage is trying to escape in a plane and Travolta stops him by ramming a helicopter into it:
Travolta prevents the plane from taking off and forces Cage to crash into a warehouse made entirely from fireworks, apparently. If you seriously think, even for a second, that a real law enforcement agent would actually try a stunt like that then you're hugely misinformed about how much money they make.
Unless we're talking about a cop from Brazil, that is. In 2009, a police chase in Sao Paulo, Brazil, turned into a John Woo film when the cops found themselves racing to reach a plane full of smuggled goods that was about to take off. And then it got really crazy.
As the car closes in, the officer in the passenger seat leans out the window and aims his rifle ... but then the driver says, "Don't shoot, I'm going to hit the wing."