That last sentence is really nonsense. What you mean is, no one should combine those two stances, because to do so is inconsistent at best. But that doesn't mean that it doesn't happen, or even that the people who do that are in any way exceptional in their hypocrisy.

No matter which religion you look at or which group of believers you study (including non-religious "beliefs" or adherences like, say, veganism), there will always be some rules or doctrines that people adhere to far closer than others. Among those that are most closely adhered to, you'd have the things that most strongly distinguish the religion in question, like the dietary laws for Jews and Muslims, and also things that align with pre-existing personal or culturally ingrained preferences or aversions - like the distaste for condoms.

But the laws banning things which are almost universally tempting, and against which you can't really create a lasting cultural aversion, such as extramarital sex (or, say, gluttony), well, it's hardly a surprise if those are less convincing and people try to sneak around them more. But just because they break those rules, doesn't mean they then think "while I'm at it, might as well break those other rules too". A Jew or Muslim who generally eats kosher/halal, but then commits adultery, would not consider that a reason to suddenly stop eating kosher/halal as well.

And then of course there's the issue that by opposing condoms (and for that matter other forms of birth control) so strongly, the Catholic Church effectively keeps them away not only from its own believers but also from many who aren't practicing Catholics, but just happen to live in predominantly Catholic regions or countries. America is quite an unusual case in having such strong religious diversity nearly everywhere due to all the immigration; in most other countries, that really isn't the case (it's admittedly becoming more so in many places, but there's a long way to go).