The only thing I’ve seen that uses normal keys are standard fleet cars. We call them GOVs (government owned vehicles, pronounced Gee Oh Vees) or TMPs (Transportation Motor Pool). Also sometimes called GSAs (No idea). These are the normal, everyday, off-the-lot, cars, trucks and vans a unit might have. Recruiters, for instance, aren’t driving around town in hummers, they have normal civilian cars that use normal civilian keys.
Everything else uses a push-button or a switch.