I think that a potential quick answer to this question is that people already do. There are people who "get by in life without developing an active relationship with God through prayer and receiving the Sacraments frequently." I think that the question operates on a faulty premise in that people do "get by" already and have not done what is being asked in the question. It makes the presumption that religion is on the same level as oxygen, and while many would view it as such, I am not entirely certain that one can make the link that it is. As previously pointed out in the previous post, I think that the other element in this question is that others believe in earnest that their religious traditions are as much needed to "get by" than those who would feel the vital importance of the Sacraments. In the end, I think that the question is a challenging one to answer because of its challenges in premise and the fact that it can be taken in so many ways and in so many other forms. It is here where I think that, at best, some type of differing answers could be offered, but nothing in the realm of the definite. It is here where I think religious studies could be quite powerful in being able to contrast how other spiritual traditions feel that their own elements of "an active relationship with God" is just as important as one who feels the need to "get by" with reception of the Sacraments "frequently."
This is a very difficult question to answer specifically because with any question like this that has to do with people's religious practices the answer is incredibly personal. I am sure that there are people who would argue that it is vitally important to develop an active relationship with God through prayer and to receive the sacraments, but the truth is that there are lots and lots of people who don't do this and manage to survive and even thrive.
So, I think we have to understand that people's religious beliefs and practises is a very subjective, private and personal matter to them alone and that we cannot make universal statements about everybody. For example, Muslims would definitely agree that prayer is important, but obviously they would disagree with the Christian sacraments. Other people, who don't necessarily ascribe to a particular religion, would completely disagree with this statement. Therefore you are only going to receive a personal response to this question.