graduate school - Are Identical Make-up Exams Fair?

I recently took an exam, and our professor told us that we should submit our question sheets since 2 other students in our class are going to take a make-up exam. We were also told that we were not allowed to talk about our exam while the other 2 are around. I presume this means that their exams are going to be identical to ours (For the sake of argument, let us assume that this is the case, and it is not in fact a strategy or something of our professor).

Our class is on weekdays (MWF for 1 section and TTh for another), but we had our exam on Saturday afternoon. Since we all have class on Saturday morning, it is okay to have an exam on Saturday afternoon since we would already be on campus. Apparently those doing the make-up exam have conflicts with their plans for Saturday afternoon which the professor accepts.

Essentially, we can't tell them the contents of the exam. Our professor claims that this is so as to not compromise the integrity of the exam.

So here's my first question:

Is it fair to the students taking the exam earlier that the make-up exams are identical to the original?

We are grad students of mathematical finance.

Expansion:

It seems to me that the fact that it is too easy for the two others to find out the exam questions should be reason enough for our professor to give a different and possibly even harder exam and that doing otherwise is in itself compromising the integrity of the exam.

If it's not compromising the integrity of the exam, why not just have the same exam every year and collect the question sheet from students (which, cmiiw, actually doesn't really do anything since we can just copy the questions on a bond paper and bring the bond paper home)?

See possibly related question.

Second question:

I seem to recall that department policy is that make-up exams are "generally" (exact word in undergrad syllabuses but not in our grad syllabuses which makes no mention of such) more difficult. If the answer to the first question above is yes, then does it follow that the "generally" should be removed?

P.S. I truly cannot imagine how difficult it must be to a mathematician: research, teaching, consultation, conferences, etc. Thus, I am aware that it is no easy task for a teacher to just come up with a make-up exam, but nevertheless for the sake of maintaining the integrity (maintain is not compromise?) of exams, I believe this should be done.