Even if you’re available weekdays, the kids are not (they’re in school)
Blanket statements like GP made are not true for everybody.
If I (and my partner) had the opportunity to work less during weekdays and more in the weekends I'm still not sure we would do it. There is something mental about it for me at least.
Besides she's a nurse, so she works every third weekend anyway. In that case weekends become really important for me.