I think you are a little mixed up
No one is questioning your right to air your opinion, people are merely questioning what you say when you give your opinion.
The way in which people do that on a forum is by giving their opinion.
These differences of opinion then lead to debates.
Most problems tend to arise when people fail to accept that other people have different opinions from them.
On your final point please tell me that you are not seriously claiming that everyone else agrees with your opinion because they dont post?
Please tell me you dont honestly believe that.
I do believe that. Now, hear me out, the reason is because if you hear someone spouting nonsense the natural human reaction is to state your point that kills their point. It's a natural instinct in humans from the day of a caveman when hunting and impressing the member of the opposite sex. Now, it's a similar situation here. People can't argue by point that LFC were shocking today and the manager made some horrific decisions, hence they agree.