Where does it state that not being married would be mentioned? How common was the names Jesus, Joseph and Mary back then? Were all the disciples married? If not is it significant that it’s not mentioned but it is for Jesus?
Marriage was the norm. Not to be married when you're 30, in that day and age, would be remarkable and be remarked upon, unless you were a member of some ascetic order. (Jesus reportedly spent some time studying with the Essenes, but was not an Essene himself.)
The names Jesus, Joseph, and Mary were not all that common, from what I understand. Jesus's name (Yeshua) especially. To have all three of these names, plus James and (later) another Mary in one family would be fairly uncommon.
A couple of the disciples were known to have been married. But their ages are never mentioned, nor the marital status of most of them, so we'll never know. But again, if not, it would be unusual after a certain (fairly young) age.
The story is about Jesus, with the disciples as featured players. Nobody really cares if Matthew or James or Thomas was married.