Why does a car need wheels or mobility?

Some people park their broken-down cars on the lawn, and we still call them "cars."

Why don't we expand the definition of "car" to include other lawn ornaments, like plastic flamingos?

Think about it. When the government recognizes an object as a car, it requires the manufacturer to submit the car to millions of dollars of rigorous safety testing. The feds don't bother to submit plastic flamingoes to any rigorous safety testing.

Children play on front lawns. If the children are playing in an old beat up Chrysler that's sitting in the front lawn, they are protected by millions of dollars of safety testing. Children who play with pink flamingos have no such protections.

Why do we discriminate against children who play with pink flamingos, but not against children that play in broken-down cars?