I think we've got a lot of misperceptions going on. As for the Malthusian overpopulation craze, that idea is on the wane. The birth rates of industrialized nations are in decline and more recent stats show that countries with large populations have stabilized. While there have been local famines and shortages, globally more food is produced than can be consumed. There are many factors at work, here--subsidies, unforeseen consequences of regional and global trade agreements, education, rise in the standard of living globally, etc.
Yes, food can be pretty readily produced with modern agriculture, food shortages are only a concern in the third world; but it's hardly the only resource of concern. The one of most concern that pops into my mind is energy. We can barely keep up with the energy demands of modern society and more people use more energy resources as readily as they use more food. In fact, starvation in the third world can probably be attributed more to energy shortages than food shortages. We produce enough food to feed the world, but the cost of transporting it from, say, the United States, the number one exporter of agricultural products, to Africa is prohibitive, especially when people in Africa can't afford to pay for the food. Recently, when oil went up to nearly $150 a barrel, an estimated million people starved to death because the UN had to reduce food shipments due to budgetary concerns.
Instability in the petroleum market has hardly helped things, it may lead to the development of renewable energy, but those forms of energy are even more expensive. We can talk about reducing energy usage, but any meaningful restrictions would stifle the economy and lead to even greater problems. The fact is that energy is a limited resource that our society relies upon and it being stretched to the limit because there are too many people: overpopulation.
Families that have too many kids may have to rely on the government to help support them, thus causing economic injury to the rest of society. Kids may be denied educational opportunities because their parents have too many children and cannot afford to help them; this reduces their overall earning potential and reduces their potential contribution to our economy. Jobs are also limited, some may expand with the population, but jobs such as mining, farming, fishing, and most jobs that deal with the acquisition of raw materials (which, with the exception of farming, tend to be some of the better blue collared jobs) are limited not by the overall population but by the availability of a specific resource. And many industrial jobs can also be limited by the availability of these resources.
Combine this with the increasing automation of many industries, the demand for labour itself, the demand for extra people, is greatly diminishing (consider how many people today are required to farm ten thousand acres of corn compared to farming the same amount 150 years ago). In some fields, a couple people today can do the work that would require thousands two hundred years ago.
At the end of the day, there are many limited resources, not just food, and they all must be taken into account in considering a sustainable population. And despite the problems with decreasing a population (disproportionate costs to care for the elderly, restructuring economies to work more efficiently), in some instances it's more than worth the temporary difficulties. The United States may be sustainable with 300 million people, though we'd probably all have a higher standard of living if the population were half that, and I question if it's sustainable with 600 million people. Countries like China are not sustainable with their current population, in a country with some of the most fertile land on earth, they still struggle to fight off starvation in some of the poorer regions. The Netherlands has reclaimed a quarter of their country from the Sea, but land is still a scarce resource causing cramped and overpriced living conditions, their current population is barely sustainable, population growth would not be.
I think what is the key issue here, with contraception, is that the primary purpose of sex is the creation of children. There's no law against sexual abstinence, but it is a matter of grave concern if a couple wants to have the sex without having the children. And there are many reasons to have children, and as many as God gives.
As for socio-economic elitism in Orthodoxy, this is utterly ridiculous. There's no more of it in Orthodoxy than anywhere else in America. Perhaps it is an American problem, but I think that view would be less than accurate and certainly not generous.
Why does this make a certain song from Monte Python's The Meaning of Life
pop into my head? Now I'm stuck with it...thanks a lot...