Hi Scully,
If it's just a show, or a matter of going through the motions, without actually knowing what they are agreeing to, it could be a case of a person's baptism being invalid (best case scenario if they want out later), or it's just one more example of blatant hypocrisy in the organization.
The prospective publisher is well aware of the questions that will be asked. When they become unbaptized publishers they are given a copy of the Organization book, the baptismal questions are located in the back of that book. They have the opportunity to review the questions that will be asked and the scriptures supporting the Watchtower's teachings on each question. Again, the extent of their understanding rests on whether or not their Bible study conductor (or parent) and the student themselves have put sufficient effort into learning the Society's teachings.
The elder reviewing the questions is not there as a strict tester, at least not with the experiences we have had. The brother who went over the questions with a member of my family, asked the questions then after the answer was given added explanatory information or asked his own side questions.
Seriously, if they are baptizing 6 and 8 year olds, do those BABIES really have the kind of understanding of doctrine to teach other people The Truth™? Are they capable of making what is clearly an ADULT decision?
Six and eight year olds have parents. It is the responsibility of the parents to make sure their child understands. If the child's parent is not involved than the child's Bible study conductor is responsible for making sure the child understands.
My point is, the Watchtower provides the materials, procedures and requirements by which the prospective publisher should be trained and informed. The fact that the Bible study conductor, the student or the elder asking the questions may not follow the guidance provided is something which is not the fault of the Watchtower.
IW