It also stops the panicking "has anybody seen my car keys?" that we all experience.
Another reason the keys are reluctantly removed at times is because owners find it very difficult to turn the ignition key after inserting it back into the ignition barrel.
Fear not, it's a common problem and one that can usually be easily overcome.
By simply getting into the habit of lightly jiggling the steering wheel side-to-side to remove any load being placed on the ignition barrel by the steering linkage itself, the ignition key should turn a lot easier.
Or often, you can feel a springy-type movement when the steering wheel is turned in one direction.
By holding the wheel in the loaded position, this will also release the tension on the ignition lock and allow the key to turn more freely.
Older vehicles usually have a very narrow and thin ignition key so over time they can twist and finally break if consistent force is being applied when turning.
Most of the ignition keys that suffer in this way are from the older fleet and are not part of the engine immobiliser system so the local locksmith should be able to quickly provide a cheap replacement if there are signs of fatigue with the key.
Wear in the ignition switch itself is also not uncommon in older vehicles and if left for too long can lead to a number of problems, including lack of power to the starter motor contacts when the key is turned to the start position.
To help increase the life of an ignition switch/lock assembly, the fewer keys on the actual key ring the better. The more ongoing downward load that is applied to the ignition switch assembly, the more premature wear there will be in the internals of the switch.
As a general guideline, a total of up to around four keys is considered acceptable for an ignition key ring.
Replacing the ignition lock is neither cheap nor straightforward.
As an anti-theft deterrent, ignition locks are normally secured to the steering column with tamper proof or sheer bolts.
During assembly, the bolts are tightened to a torque setting where the head of the bolts break off making removal at a future time difficult to say the least.
So if you have an older vehicle in your current fleet it would pay to check the condition of the ignition key itself and if necessary go get a new one cut.
And while you're at it, have a look at the number of extra keys or accessories that make up the total key ring. Lightning up the load may help save you a few dollars during ownership.