A: This is an odd case, as normally Stop That!, the counter-Action Surprise (aka Belay That!) could not be used against what is essentially a Rule-that-gives-a-Free-Action, but, in this case, since there is literally an Action card involved, Andy says, yes, you can use Belay That to prevent its effects. HOWEVER, normally, using Belay That on an Action would have you throw that Action away, but, in this case, since the Action is attached to Let’s Keep Doing That, it stays in play, though it may not be used again on this turn.

It could also be stopped by the newer Surprise called No Free Lunch! which counters the use of any Free Action (though, again, it doesn’t discard the card being used, it just prevents the person from getting to use the effect.)