The drawback is if you left your keys on the bench in the garage next to your car. You get in, push the button to start, then drive off. Now you can't get back home. At least with the physical key you are guaranteed to have it with you.

The other thing -- do the key fobs have an on/off switch? If not, you wouldn't be able to have a spare "hidden" under your car somewhere (yes this is insecure anyway, but it works for most people).

I think (some) cars actually know whether the key is inside or outside the vehicle and can't be started if it's outside.

People bring this up as an objection all the time, and I think it always comes from people who have never actually had a car with this feature. First, as mentioned earlier, every car I've had with pushbutton start will not let you start the car unless the key is INSIDE the car. Second, if you try to drive off with the key NOT in the car, they've all made an alert sound and shown a message on the display that the key isn't in the car. It's certainly possible to intentionally drive off without the key, but I don't think it's possible to do so accidentally (or if you're so inattentive that it is possible, you probably shouldn't be driving in the first place).

> do the key fobs have an on/off switch?

Pop out the battery. You don't need the battery to use the hidden spare if you lose your key: there's a physical key hidden inside the fob to unlock the door, then a slot on the dash to stick the whole fob into to start the car. It's there so you can't be stuck unable to start your car when the fob's battery dies.

http://i.imgur.com/uBeach6.jpg

I actually got curious and have a friend hold my key outside the car while I try to start the engine, and I couldn't. The car correctly detects that the key is not inside with me.

Also, the dashboard will always tell you if you are inside the car but key is not detected. So even if it miscalculates where the fob is and let you start the engine, that key-not-present light will be on as you drive off.

Most key fobs have some kind of failback system that looks like a real/normal metal key.

I suppose in very cold places, there are issues I haven't thought of. Honestly though, I think it's more about how novel and shiny it feels. It makes (made?) the car feel a little futuristic in most cases. A sort of signal a potential buyer that this is the next generation of car..

I think the trade off makes it not worthwhile. If it's optional, I prefer a normal key.

OTOH, There are lots of other cool gadgets that I'd like to see. A car that remembers everyone's seat position and mirrors, that's progress. Manual transmission, normal key, smart seat. That's my niche.

I have a Town and Country and the key never really leaves my pocket. I can touch the door handle on the driver's or passenger's side and unlock all the doors. I thought of it as a novelty at first, then in real life I realized how handy it is. Maybe it's just because I have kids and my hands are usually full but I use it all the time. Also it is nice to just push one button on the door handle to lock all the doors.

Another benefit that I know BMW has (and probably others too?) is that I can press-and-hold the unlock button as I approach the car and the windows roll down. Keep holding, and the sunroof opens. In the summer, it's a nice way to cool off the scorching-hot sun-baked interior before getting in.

This isn't an attack against cars that you have to press a button on the remote to unlock the car. It's an attack on the cars/remotes that are just near each other and unlock/start.

The simple solution: Just go back to pressing a button to unlock and putting the key in the ignition.

If the manufacturer really wants to keep the feature, then they could switch to those keys that flip out like Fiat has and just turn off the near-unlock functionality on the remote when the key is folded in.