These fundamental beliefs are:
God as triune God, the Father, son and Holy Spirit
Sacred Tradition and Sacred Scripture
SIN: Original and personal
Sacraments: baptism, Eucharist, reconciliation, confirmation, marriage, holy orders, annointing of the sick
Human destiny: Heaven or Hell and the final judgement
Of these dogmatic beliefs, some are more easily understood at face value while others need more study and prayer by the believer. It is all up to the individual and their ability to grasp each belief.
But from these beliefs come the way of life, living the faith, being who we are through the Catholic Church. One can not be a Catholic and not know that we make a conscience decision to either sin or not by our thoughts, words, and deeds. A Catholic cannot attend Mass receiving the Holy Eucharist without a firm belief that it is Christ's own flesh and blood transformed from the host and wine that we are receiving. Hence, a Catholic who receives the Holy Eucharist in correct preparation cannot go through the daily routines without feeling that Christ is within them giving them graces to carry on righteously.
Cardinal Chaput stated recently that these people are the product of poor catechesis from the Catholic Church in the past decade. He's right, the Baltimore Catechism hasn't been used in mainstream Catholic culture for years! The Catholic Homeschoolers are using it and have been. Our children get it along with their parents who are teaching them through the Baltimore catechism. It's basic, boring, to-the-point, easy to understand, rote, whatever! It's what is needed. It's what is missing.
These Cafeteria Catholics are hurting our Church, they are the examples for the world to see. They are NOT the true Church, they are NOT what we believe.