The defense given, on both the left and the right, for ignoring Church Teaching is often "Prudential Judgement"- that is the judgement of the prudent. But the meaning of the word "prudent" has changed over the centuries. Prudent today often seems to mean selfish- it certainly means self-sustaining. But this was not always so.
In the world of contraceptive mentality, having a small family today is prudent, for it means that everybody in the family can be fed. 200 years ago this was not so; having a large family was prudent, because it increased the likelihood that the whole family would be pulled out of poverty by one of the many children striking it rich. Thus, 10 children in a family was not uncommon, and was an investment in the future, not the wasted money that it appears to be today.
Likewise on the other side of things, almsgiving before Ayn Rand was seen as a prudent measure; for he who closes his ears to the pleas of the poor will one day cry out himself in need, and have nobody around to hear.
Thus I say, those who cry out for prudential judgement in support of sexual or fiscal hedonism, are in fact not exercising prudential judgement, because they themselves are not prudent.