Compress ignite has a point. In my years in the garage business I replaced a few ignition switches usually on vans owned by contractors who always had a big wad of keys hanging from the ignition. The extra weight wore out the switch.

Now I keep all my car keys on their own key ring, no more than 2 keys to a ring.

Of course this only happens after many miles, usually over 100,000. So if you are not going to keep your Benz that long or you don't care if the key wears out and your car won't start one day, don't worry about it.