My wife's family had a weekly ritual which included Church, followed by Sunday brunch. While her memories of the Church portion are perhaps less warm and fuzzy, the memory of the family meal which followed is one that is close to her heart. We have now, nearly 30 years later, inadventently revived the tradition in our own family - herding the kids out the door every Sunday around noon, and heading to our local Greek restaurant to feast on salad, grilled octopus and fish, horta, and saganaki. The staff treat us like family, we eat like kings, and the outing guaranties us 2 hours of peace in the afternoon when we all tuck in for a nice, food (and yes, wine) fueled nap.
But there are other, less obvious and perhaps even greater, benefits to the ritual. First and foremost, it ensures that we sit down for at least one relaxing meal together each week. Weeknights my wife will often eat with the kids while I work, or I'll feed the kids early and we'll finally crash at the table for a quick bite after the kids are in bed - but it's rare that our schedules converge in a way which allows us all to be around the table together. The kids are still young, and for the moment our Sunday lunch conversation is fractured at best, but I suspect that as they get older this will evolve into one of our only chances to actually communicate as a family, on neutral territory.
Secondly, the outing is an opportunity for basic socialization, which seem to have fallen by the wayside today: the kids need to dress up if they want to come, and once we're there they have to sit quietly, patiently, and wait for their food. They have to ask for things politely if they want to be served, and they are expected to use utensils, and not slurp, drool or fidgit their way through the meal - details we often forget (or are far too exhausted) to enforce in the privacy of our own kitchen.
Finally, they learn to appreciate the gift of a great restaurant meal - and having spent thousands of hours preparing meals for other people, and their drooling, slurping, fidgety kids - this is of particular importance to me. They see the kitchen, the guys working their asses off to get the plates out. They know the servers, and are taught to respect them, and thank them, and appreciate the luxury of being served a meal - and they are reminded that it is in fact a luxury, a huge luxury.
So our family tradition is an adaptation of the one my in-laws started three decades ago, but the fundamentals of it are the same: once a week my wife and I get to enjoy the reward of a meal that we don't have to prepare and clean up, while our kids get a crash course in being decent human beings - and possibly, hopefully, some memories which they too will cherish fondly 30 years from now.