There could be a simpler explanation: the Justices are asking the side which is inherently unlikely to win more questions because they have a greater need to ju

There could be a simpler explanation: the Justices are asking the side which is inherently unlikely to win more questions because they have a greater need to justify their case. If you're arguing what is likely to win by the logic of the status quo or dominant paradigm, there's almost no need to state your case - the Justices will already know the logic and arguments behind your case. If you're fighting from the opposite side, there are a lot more questions, clarifications, etc. that need to be made to understand your position. And you're still likely to lose even if you've made a good case because you have the inherently weaker case. Basically, what I'm arguing, is that the Justices generally know the arguments for the stronger case and so there isn't a lot of questions to be asked, but want to give the weaker case an opportunity to make their case and prove that they, in fact, have a stronger case. However, it's unlikely coming from the weaker side that you'll have the stronger case in the end.