Boeing doesn't have it's own runway exactly; what they do have is property right next-door to both Paine Field and Boeing Field. You probably saw Boeing Field since it's only about 3 miles north of SeaTac, but I've come in on approaches to SeaTac where you can see both of the other fields.

I have a friend with a 6 cylinder Mustang and watching the way he drives, I'd be willing to bet I get twice the mileage he does.

Do I know you? :)

The V6es can be thirsty if you've got a heavy right foot, but mine still gets up around 22 mpg, and it's over 20 years old. Sure, it's slow, but at least it's a good lookin' car (Unlike some of the junk being slapped together these days...).