I agree. I did maths last year and as a mature student I can safely say an average person will not use 85% of it. The maths exams were totally catered for those going onto university. The level of knowledge was ridiculous for a general certificate in education, and most of it belonged in a specialised A level.
Remember the GCSEs are controlled by the employers, they dictate the level of difficulty. Unfortunately before the 9-1 system, the employers complained that school leavers with high grades didn't know the simple every day stuff, thus the exams were made harder. Personally, I think they have gone too much the other way, being harder then need be.