I grew up in a world where men didn't have to ask.
That may have been a world where on average, men were more dominant, women had been taught to be more submissive, and many men may have engaged in joint decision-making with their wives but were less likely to mention that to others as it might make them look weak. Perhaps today's man is, on average, less macho. Or society appraises men differently.
There are a range of potential factors. Consider:
1.) More divers are men.
2.) I wonder if more male divers than female divers are married to a non-diver?
3.) Plenty of men would veto solo trips to exotic places by their wives. Perhaps in our culture for a man to say 'my wife won't let me' is a kind of self-deprecating humorous chivalry that he 'lets' her have this power, whereas if a woman said her husband didn't let her, others might see her as 'controlled,' powerless and borderline abused?
4.) I wonder if more male divers are interested in solo trips to pursue their interests (e.g.: scuba, deer hunting, white water kayaking, skiing, etc...)?
5.) Wonder which sex is more worried about the risk of the other cheating?
In our family, I'm currently the breadwinner and my wife doesn't try to veto my diving (except she fought solo diving pretty hard; I basically indicated oh yes I will, and did, and she gave that fight up). But I consider the money 'ours,' not just mine, family money, so running off to blow, oh, say, 3 - 4 grand on myself without blessing my wife & our little girl with it merits some fore-thought.
So she sometimes heads out on a girl's road trip with her old high school buddy. Sometimes I plan trips where they can go (what my wife calls a scuba trip disguised as a family vacation).
If you do the scuba trip disguised as a family vacation, book your week off airfare Saturday to Sunday, 8 days, and spend Friday AND Saturday with the family. Just one 'family day' and I get the stink eye.
Richard.