I guess the word fake gets thrown around a lot because there's so much of it going on.
I knew this guy who after a truck accident sued for permanent back injury and won that and also was getting SSDI. He would come over to my house and be laughing doing cartwheels. A few bad apples ruin it for the rest of us.
It's because of people like him that we have to leap through sometimes mind exploding hoops. But just like Jenn said. I too wonder about those who say "fake" too much...

P.S.: This happened years ago and I don't know whether this is still going on or he got caught...