Wonder who the irresponsible wife marrying him
You can't just assume she is irresponsible because the dad is. This could just as easily become a case of she just found out how shitty a man, the man she married is.
A mom can not be held responsible for what a father does when he is alone with their child. It is 'their' child, not hers alone. Dad has as much right to go out and do things with the baby too. Mom should not have to be worrying about what dad is up to when out with the baby.
He probably braught the baby, as an excuse to go to the club, and not have his wife question his whereabouts.
The wife made the mistake of marrying an irresponsible husband. It doesn't make her irresponsible to trust the man she had a kid with, to make good choices when he is alone with the kid.
My next question, from personal expierience might be, was this a case of parents who are split, and this was dad's time with the baby when he made this decision? As a full time parent, sometimes it was just a blessing dad took the kid for a bit so she could have a moment childfree to not be responsible for a baby for a moment. She shouldn't have had to worry about this happening.