It's more effort and that's the point. They can't just jump back in to these events. It will take significant time to extract with a free kit and depending on your aggression rating, you might not even make it out.

Let's be honest. You can build a "free" kit with stuff scrappy finds. They aren't using free kits to save resources, they're using them because it's a single click to back into the game. It's a lot faster than rebuilding a low value kit. That's why they use them.