What exactly do you mean by "community property"? Sorry, but I'm not familiar with how property laws work in Spain or Latin America. But that phrase
in English seems to carry with it implications that I don't think you're trying to imply.
If what you're referring to is a kind of shared property between the husband and wife, in which the husband and wife are both the owners and are on
equal footing, then I can take a guess as to why the Church has not required this. My guess is: because family structures are hierarchical; the husband and wife are not supposed to be on equal footing. The wife has no right to sell off the family property without her husband's permission, nor does she have a right to spend the family income howsoever she pleases. These sorts of decisions fall upon the husband who is head of the family. (And the wife certainly has no right to divorce her husband, let alone keep half the family property for herself.) So it makes sense if the Catholic Church does not force the husband and the wife to convert all their property into "community property" (as defined by these laws) upon marriage, as that would more or less undermine the family's natural structure.
Do you have any citations from a Catholic source for that?
Maybe somebody else does, but I do not. It's just that this is how marriage has always been understood. "Wherefore a man shall leave father and mother, and shall cleave to his wife: and they shall be
two in one flesh." (Genesis 2:24) The husband and wife are no longer two separate autonomous individuals, but are a single family and must act as
one family unit. To say that the family's head should be entitled to his own property is about as crazy as saying that a man's physical head should be entitled to its own separate blood supply.
Because I've worked hard and long, I bought it, I've been making payments on it, I've been maintaining it and I don't want to risk losing it if there is a divorce. Divorce is already painful, so why allow it to be worse by voluntarily putting myself in a position to lose more money? Trads sometimes get divorced, in case you didn't know. Can I ask you why you want my future wife's name on the deed?
This is completely the wrong attitude. First off, you should be planning for marriage, not for divorce. Second, that's the chance you take when you get married, and is why you shouldn't marry somebody who is foreseeably going to turn against you and proceed to abuse the legal system in order to take what she's not entitled to. But marriage entails sacrifice, and it's not going to work if you're holding back (financially) out of fear that something might go wrong.