Dimitri C.,
There is another point of view I would like you to consider.
This service is provided to you free of charge. The people who help you, they do it free of charge. The questions and answers are all available free of charge. But "free of charge" refers only to financial remuneration. There is one way you compensate the system and its users for the time and expense they put into it; by providing content.
Content doesn't just include the questions and answers you provide, but the value-added information you provide by participating in the community. Your votes, your comments, your profile, your reputation; they all add value to the system. And accepting answers adds value to the system.
Now, no one "requires" you to participate in any of these activities. They are strictly voluntary. But the behavior of the system is designed to encourage activities that are best for the community.
Regarding "accepted answers": You choose not to participate because you do not agree with it. That is your choice. But you are also, in a sense, abstaining from providing a bit of "compensation" that users might expect for their efforts. Users have a right to know that up front. Not have it "hidden" from them.
In one of my comments, I quipped that hiding your your acceptance rate is like saying, "I don't like my credit rating. How can I hide it from lenders?" I feel that that analogy is apt.