Exactly. My car has adaptive cruise control. In slow traffic, if the car in front comes to a stop, it'll also stop. But what happens if it's turned off? I honestly don't know and don't have the balls to find out, because so far it just keeps getting closer to the car in front. So if I accidentally pause it then drive the same way I would with it enabled, I might(?) rear-end someone.
It'd be the height of stupidity if it does just keep rolling forward, but who knows...
When I bought my last car, I was sort of excited about adaptive cruise control and lane keeping. But maybe because most driving I do (which isn't a huge amount) is on pretty busy roads I've sort of avoided really using it.