Just spent 8 years in Army Aviation, and I noticed that they fill the helicopter tires with Nitrogen. I asked why, and they said that Nitrogen does not expand and contract like oxygen does. Or the equivelant of finding soft tires during the winter time, or over inflated in the summer time.
Nitrogen is more stable than air, does not have the same rate of expansion when exposed to heat, and the reason why is used in aviation. During landing and hard braking, the brake system in commercial airplanes will reach tremendous high temperatures. Imagine trying to stop an airplane with 319,000 lbs of weight at 145 MPH!!!
A tire filled with air would expand and blow-out almost inmediately.
Also, it is one of the reasons why is used in road racing and oval race cars; the tire pressure is more consistent. It is not used in drag racing because you want the tire to grow during the run, therefore, air is used.
You can have pressurized air also in bottles or containers the same way as Nitrogen. Every Fire Station and Fire Truck has bottles pressurized with air. The breathing equipment and bottles used by fire fighters contain plain air; Oxygen is combustible and explosive, therefore is not used in bottles.