I believe the reasoning behind them working on fuel injection only, or at least being advertised that way, is because under most circumstances a carb needs the pedal tap before startup to set the choke and give it a squirt of fuel to prime it. Of course sometimes during warm weather and such we can get away without tapping the pedal first, but when the remote start is really nice is when it's freezing out early in the morning and they'll never start dry on a cold day.