Your friend's strict regime may be more to keep herself in some kind of control and order, than anything to do with her children. Bringing up children is very tough (as you know) and some parents, especially the mother, who bears the brunt of everything, finds adhereing to a strict regime necessary to keep sane and to keep going without it all falling apart!
The problem is, that as soon as a 'spanner is thrown into the works' ie, some event or happening occurs out of the boundaries of the regime, her whole life maybe thrown into turmoil and her coping mechanism gone!
It may also be that your friend never really liked going out, so now she has the perfect 'excuse' to stay in, whilst hiding under the guise of being a 'wonderful mother!'
The problem is, it's not real life, with all its ups and downs and unpredicatability.
Your way of parenting seems much more livable!