So if anyone in your group doesn't care about your question, you're out of luck. Reframe: I don't know why I even bother.
So if anyone in your group is more interested in a different question, you're both out of luck. Reframe: Sorry, class, we're out of time.
Yes, it's funny how many ways a bad idea can be framed differently.
The sister comment from another teacher brings facts to the table that explain the intent of the exercise, which is limited in scope and aimed for a specific purpose. Good or bad it is a game to attempt to teach kids it is ok to admit they don't know and to ask for help from their peers. If you consider how often and how ennervating it is when our adult colleagues can't admit not knowing, I think you can understand why someone crafted this exercise.
The former process is controlled by the group; the latter, by the individual.
Hell, it could be an exercise to teach students the dangers of group think. It would be intellectually dishonest of the author to frame the situation in the way that she did, but we have no idea of the context. Did the author watch the whole class and speak with the teach afterward, or did she just observe the class for a few minutes?
Without more context you just don't have enough information to make such a damning judgement.