Not all church elders or ministers or pastors are married, and definitely not those in the catholic church. So yea.I don't think it's quite right to say that "in Christianity, singleness is preferred, so you can serve God without distraction."
Even Jesus said that celibacy isn't for everyone.
And consider all the things Paul said. Paul's writing on this issue is pretty nuanced. In 1 Corinthians 7 Paul says he has no "commandment from God" about this. Paul says that he wishes that everyone was single like him ── not that God wishes it. He says that he, personally, is content with being single ── but he admits that not everyone is like that. He says that it's good to stay single, but that it's better to marry if you have strong desires. Paul "supposes" that it's better to stay single because of "the present distress," some crisis that the church in Corinth was dealing with at the time. He says you're not sinning by marrying. Paul says a widow would be happier if she stayed single, but he admits that this is just a personal opinion. Evidently, many people are not happier being single. In 1 Timothy 4:1-3 Paul also condemns people who forbid marriage. And if Paul wrote the Book of Hebrews, then he also said that marriage is a good thing.
Also, a lot of the time, people say that being single is good because you can devote yourself more fully to God. And when you're dating or married, you, apparently, can't do that. A lot of this comes from 1 Corinthians 7:32-35. Paul basically says here that an unmarried person is devoted to the Lord and not distracted by the needs of his spouse. This is then interpreted by some to mean that a person can do "more ministry" as a single.
I don't think that's what Paul says here. I mean, if that's the case, why are all the pastors and church elders typically married? Did they make a mistake? Is marriage getting in the way of their ministry? What Paul says here, I believe, is that if you aren’t distracted by the desire for marriage, then maybe you have the gift of singleness.
And, of course, in English, "distracting" has a negative connotation, so we often bring that into play when reading or teaching this passage. But it seems more like Paul might have merely been making the elementary observation that marriage, or the search for marriage, can place more demands on your time and attention than the life of someone who is genuinely content with being single (like Paul was) But, of course, Paul said that not everyone is like him, a single man content with being single.
Paul wasn't a pastor, he was an apostle, and an evangelist.