For me, the larger problem with questions like the ones you described are that they encourage muddled thinking and require that kids make unjustified assumptions. If a question is much worse than the usual bad ones, I might bring it to the teacher's attention, but my usual tactic is to go over the flaws in the question and teach my kids how to recognize them.

Last night DD had a probability question: There were five numbers in a bag (0-4), and three were picked and not replaced. Zero wasn't picked. What was the probability of picking a 2 on the next turn?

DD was flustered because she'd removed the 2 in our mockup of the problem. But she wasn't sure what to think. "Should I put back the 2???" I explained that it was a bad question and asked her to think about different possible scenarios. She ended up understanding that because the question didn't specify whether or not the 2 had been picked, there were two possible scenarios: it had been picked, and the probability was therefore zero, or it hadn't, and the probability was therefore
one-half.

I hope that these lessons will ultimately do her a lot of good by teaching her to recognize bogosity. I don't know if I've helped you; it's really not an easy question.