I've lived in Spain for 15 years, and have a 4yo DD with my Spanish husband. The view that Spanish children are better behaved just isn't one that I recognise. Yes they're involved in everything from a young age (bars etc.) but they're often running wild because the adults aren't paying much attention.
On the other hand, it's true that there is more of a community feel to child rearing, and I think a lot of that is down to people spending a lot more time socialising outside their homes (homes are usually flats and the weather permits spending time outside!) People don't worry about telling off other people's kids, for example.
Also, because people have their evening meal later, lots of children eat earlier, separate to their parents. Although it's true that lunch is usually all together. But my DD is practically the only child I know that eats the same as us and is adventurous in what she eats - there's still an old-fashioned view here, among parents and paediatricians, that children need "easy" food. Most restaurants (as opposed to local bars) have the usual children's menu of nuggets and pasta.
I see just as many kids here as in the UK sitting in buggies with a huge bag of crisps and a mobile phone spewing brain-numbing videos.