They often do, but usually couch their objections diplomatically. Students benefit from the questions in five ways. First, they tell me in their course critiques, it forces them to focus their reading. Knowing that they have to come up with a written interpretation of what they read, they aggressively look for themes, agreements, and disagreements in their assignments. Second, this leads them to approach the readings at a number of different levels as they examine the facts, scrutinize arguments, and look for theoretical assumptions.
Students are also good at calling attention to disciplinary blind spots.
Third, the questions enable students to examine the relationship between the readings and comments made by seminar members. I encourage them to take notes on who said what in seminar. They do, and sometimes cite one another in their questions. Fourth, as the course examinations are take-home, the written questions prepare them for writing about the ideas and themes of the course, by giving undergraduates the opportunity to think about what they have read, and to write about it, weeks before the first examination is distributed. Finally, as the discussions are organized around their questions, the seminar is driven by their ideas.