No matter if you are civilian, military or law enforcement. Chances are good that the firefight you have trained for will include vehicles. We are not talking armored personnel carriers or IFVs here, we are talking unarmored civilian vehicles.
No matter which environment, vehicles are usually present either as your own asset, the enemies asset, as a terrain feature or as a bit of everything. Modern urban environments are packed with vehicles, even rural areas include them. Try to remember the last day you havent seen a vehicle. I bet its been a while. In contrast, when did you see the last 9-hole-barrier while walking the streets?