I think for most people the problem isn't really the size but the fact that wacken is so mainstream nowadays.
I remember 10 years ago, you only saw guys with long hair or who were bald, there was nothing in between, because that's not metal

pretty much everybody was either wearing a cut off jacket or a leather jacket (when it wasn't like a gazillion degrees). and so on and so on.
nowdays when you look around at wacken you might as well be in a random shoping mall because you will see "regular" people, who wear a metal shirt to fit in with the crowd, all over the place.