Was supposed to do an oral exam, but was instead presented with my grade Me and a group of classmates (each of whom including myself had been active participants of the course) got called to the professors office half a week before our oral exam and were each presented with a grade. We went there together and could accept or deny the professors suggestion. 

It was clear from my friends that they were happy to accept it (the real oral exam is very difficult). I was personally very unsure how to feel about it, partly because we had just written a "pre-exam" in the morning of the same day and I had made some really sloppy mistakes. The grade I was given felt unjustified in how high it was. Of course by the difficulty of the actual exam it felt stupid in a practical sense not to accept the professors offer. I still made a meek attempt to protest, after which he insisted and I essentially made the choice to accept. Also partly because of my friends who I in the moment realised would look worse off had I not accepted.

The exam is not especially important, it is a course like any other in the end. And I know (which was the professors point) that I would have studied to take the exam and probably done ok. But I cannot shake the feeling that I made the wrong decision. Having done some thinking, it feels unfair towards the people who have to do the real test, and I imagine this situation is precisely why terms like "kissing up to the professor" exist. I feel shame because I participated very much in the course simply because I love the subject and for no other reason. 

Was I right or wrong to accept the grade?
There is no ethical issue here if no one was disadvantaged by this. Accept that grading can be an inexact science even in the best situations. The professor made a judgment about the quality of your work overall and suggested a grade. His expectations, apparently, were that the oral exam wouldn't change his judgement. Orals can be subjective in any case, and he  perhaps wanted to avoid that as well as lessen his own work load in the face of it not very likely to affect the outcome. 

This would have been different if the suggested grade were lower than your expectations or if someone else were disadvantaged by the system. 

In my own practice, I would set a grading rubric that was clear to the students. For example, 700 points earned would be worth a certain grade. Students knew how many points they had accumulated. But if someone earned 695 points they would get the higher rather than the lower grade. My assumption was (a) that the difference was not consequential and (b) minor changes in evaluations along the way might overwhelm the few points lost. Furthermore, I would occasionally let students who had already attained highest marks skip the final exam. It would give them the opportunity to work in their other subjects and was unlikely to affect anything. I think this is somewhat common practice. 

Far worse to be overly strict and leave students disappointed in the course, in me, and in themselves. 

Furthermore, if the grade "offered" was less than highest marks, you had the choice to take the exam. No harm, no foul. 

I'm not sure I'd feel the same about this if the offer was made to only the lowest performing students. In that case it seems more like work avoidance than justice. But even then, I'd want more information before deciding. 

And congratulations. I hope that you impressed the professor in some way.