Finally, someone with the right idea. I've always wondered why we don't have more restaurants with 'no children' sections. Or restaurants that don't allow children in at all. It would be so wonderful to be able to go out and eat and not have the perpetual threat of some noisy brat hanging over you (the threat, not the brat - though that too). I actually think there might be a decent business opportunity in it.
That's actually the reason why I think this restaurant owner isn't going far enough. Instead of being stuck in this polite limbo where he's making the spawners unhappy but not really offering anything to those of us who abhor the little tykes, he's essentially losing money both ways. What he should do is just go the whole hog and ban kids entirely. Hell, I'd fly down to Chicago just to go eat in his cafe. Seriously.
At this point, people who have kids will say something silly like, "What are we supposed to do - stop having a life just because we have kids?". My answer to that is: yes, that's exactly what you should do. If you're having kids at all, the presumption is that you're getting some utility out of them, so I don't see why you shouldn't have to pay a cost for that benefit. In some ways this whole thing is a classic free rider problem - society bears the cost of tolerating the little monsters, and then the parents get to reap all the benefits. Is your kid going to come look after me when I'm old and dying of cancer? No, right. Then I don't see why I should have my pleasant brunch ruined by his / her antics. On the whole, I think the world would be a much better place if people had to pay the price for foisting kids upon the world - it would hopefully make them think twice about having kids (rather than having them by a sort of motor reflex) and would mean that they would take the whole thing more seriously.
But it's not like it's even necessary for people to bear that cost. Just given the number of feckless breeders around, I'm sure there's more than sufficient market for family restaurants - satanic pits of infantile depravity where children can swarm like termites and compete in throwing spoons across the floor or screaming themselves hoarse to their heart's content. All I'm saying is, let's segregate public places so that those of us who have no desire to be put upon by other people's children can have some peace. People who have kids (or, saddest of all, people who don't have kids but want to) can go spend time in their little leper colonies, leaving the rest of us to breathe the pure, intelligent air of civilisation.
Why has this not already happened, I wonder? If you believe Coase, it should have. The reason, I think, is a social milieu where it is simply not acceptable to dislike kids. The problem, I think, is that too many people have no identity except as parents, no accomplishments that they can point to except for their children (whether having a child is an accomplishment is a question I've looked into elsewhere, and won't go into again). The result is that they're unable to accept that having children is a preference, not a value. That's why they're offended by people who disapprove of their children - they see it as an attack on who they are, rather than a simple statement of a different personal choice. And that's why it's not possible for us to evolve to a point where a coherent market for childlessness can develop. At a microcosmic level, could I walk across to a young couple who was sitting at a table next to me with their 6 month old baby and offer to pay them to leave? Why not? It's not insulting, it's pure economics. 
Obviously, I would prefer it if the ownership rights were defined the other way, and people had to pay extra to get their kids into restaurants rather than those of us who want to avoid kids having to pay extra for that convenience (I hesitate to say privilege - it should be a right). But I'm realistic enough to know that that's not going to happen. Still, it would be nice if we could have places where you could pay them to keep the kids out. Oh, there are bars, of course (one reason why I increasingly seem to be eating out only in bars / pubs - there are never any kids), but it would be nice if there were breakfast places that offered the same service.
Meanwhile, if you're reading this blog and live in Chicago, please, please, do me a favour. Go to the restaurant in the article, order a big meal, give the guy a big tip and thank him for keeping the children out.
 The other side of this social pressure is the ridiculous assurance with which people seem to assume that everyone likes kids and will tolerate them. I think people need to be educated out of this. The next time some parent lets his brat wander over to my table unattended and generally bug me I'm going to either a) teach it a whole set of choice four-letter words in my most loving voice ('can you say, "mother". Good! Now, can you say...." you get the idea!) or b) scare it into hysterics with a knife. If people won't keep their kids under control out of decency, maybe they will out of fear.