My parents are simliar/same. In our case I think it's due to old-school Italian stubborness. Mine are of a mindset that they don't call us (their kids) we are to call them and go see them each week. They have a sense of entitlement that I never thought they would. They feel that the are to be sought out daily by myself and siblings for insight advice on whatever we do and to heck with us if we make a mistake and didn't ask them for thoughts first.
I haven't purposely cut them out or anything, nor do I avoid them. They clearly don't understand how much more complicated my life is with kids, work, travel, ect. vs when they were doing the same. 2011 is certainly not the same as 1954 and while they didn't have it easy, I really don't see my parents giving me credit for all that has been accomplished in a time frame that is exponentially more difficult and moving way way faster than when they did all this.
Like has been said before, just let it go, pick and choose your battles and in my case, just ask the tough ass questions when presented with a debate or discussion. I think you'll find the questions are avoided or subjects switched.