Frankie,
The answer to your question is yes it will affect the marbling. But Kit will probably tell you he is not trying to raise terminal cattle those are what the mainstream Angus people are raising.
Joel Salatin wrote that customers vote with their dollars. Looks like Kit has earned some votes. It doesn't mean that his target voters and yours have to be the same. To the best of my knowledge there was no one holding a gun to anyone's head making them bid. If you don't like his cattle there is something you can do about it: just don't bid on them.
--Julian