You forgot about being neutral my guy. You've chosen extreme examples where people are much more likely to have a strong opinion, but that doesn't make you right.
If John is anti-anti-swimming, then John is either pro-swimming or doesn't care about swimming so long as you don't try and stop other people.
By your logic every ally is gay. If John (straight man in this example) is anti-anti-gay then he must be gay. You've reached a contradiction, thus you are wrong.