It'd be pretty easy to electrically bypass the requirement that the clutch be pushed in for the car to start... but then, the car would need to be parked in neutral (out of gear): definitely not a smart thing to do unless it's on a very level surface. There would be too much product liability, as someone would eventually get injured (and it wouldn't take long), when some moron remote starts the car while it's in gear. Anyone with half a brain could adapt a remote starter to a standard.... however, anyone with a quarter of a brain knows that it would be stupid to do so.
The best situation for a standard would be to have a remote that would recognize when the car is in gear and not start it in that situation...