The absurdity of these extremists hurts their cause. No one unaffiliated with PETA will take this poster seriously. No one will experience an epitome of epic proportions when they realize that Natalie Portman is willing to sit in piss sludge to prove that she won't wear fur.
Also, the logic is unsound. "I love animals so much, I'm going to sit in men's piss."
And the Calvin and Hobbes cartoon in the lower right makes even worse sense of the matter. Anyone who chooses to be pissed on than pissed off is undoubtably going to become pissed off after being pissed on.
This reminds me of a news story I saw when I visited San Francisco. A group of college students at Cal-Berkeley were upset that the university needed to cut down an old tree that was obstructing the construction of a new building. So they got naked and climbed the tree and refused to leave.
Their passion is admirable, but their focus is deluded.