is keyless better?

Here's what I noticed; when the key is not with me while in the car, the car won't start, but when the car is already started and I let my brother hold the key while he is not in the car, the car still drives but the warning sign on the dashboard has the "key" sign as if it's saying to me where's the key? How far can this car drive without the key with the driver? A few miles? Let's say I left the car running while I went and grabbed something and the key is with me then a thief decided to jack my car and drive off with it; how far can it go? There had to be a limit? I tried driving around in circles in the parking lot and the car was still running. I know it's only a few feet away from the key that my brother held but I'd assume the car would stop had I driven a few miles?

No limit.
The thief won't be able to start it again once it is shut down.
Before that, no distance nor time limit, until fuel tank is empty.

Yeah, it is designed so you need the key to start, but if the key is removed it can be driven indefinitely. Those keyless start systems are designed like that so if the battery in the key dies, or if there is interference or something it will not shut off your car while you are driving potentially causing an accident.

I didn't think I would like keyless start but now that I've had it for almost 6 months I love it. I never have to take the keys out of my pocket. Push the button on the handle to unlock. When I walk away the car locks itself. I have another car and sometimes I forget to take the keys out and I'm just standing here wondering how to open the door. LOL