Could it not also be that the Catholic church is opposed to contraception with the underlying belief then that more babies will inevitably be born into Catholic families?

That's an argument that has been posed many times. I suppose it could be so, but the Catholic Church is not a particularly evangelical religion. It hasn't been interested in aggressive recruiting for at least the last forty years.
What it says in the Catechism is that the "marriage act" should be open to the conception of children, because that is an inherent part of the sacredness of the "marriage act."
With a billion mermbers, does any church need more?

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From classes in Church History, it is my understanding that the development of the "cult of the Pope" is relatively new, mostly since the loss of the Papal States when Italy became a nation in the 1870s. Before that, the Pople was looked upon as just another petty European political leader, with some spiritual functions. But since the Pope ceased to be a significant political power (and since the advent of worldwide communications), many Catholics began to look to Rome for leadership, sometimes ignoring their own pastors and bishops and going to the top for direction. And oftentimes, people follow their own interpretation of what Rome has to say, which may or may not have any connection to reality. Most Catholic Church documents are very carefully nuanced and reasoned, and presented with great diplomacy. Right-wing pope-followers tend to dumb down anything said by the Vatican, so it can be contained in sound bites. Mother Angelica's Eternal Word Television Network (EWTN) is a prime offender in the U.S.

There is a careful system of division of authority in the Catholic Church. In most situations, the local bishop is the final authority. The Pope, as Bishop of Rome," is "primus inter pares" (first among equals among the bishops. The Pope is also officially "primus inter pares" among the patriarchs. Although the patriarchs of the Orthodox churches are separated from Rome, there is still formal respect among the patriarchs.
And in most circumstances, the pastor is the final authority in the local parish, and almost all Catholic functions are centered in the parish, not beyond.

-Joe-