It's a shame for families that do expect children to behave. But you can't tell just by looking.
We've been lucky to live in two other countries. One, a Mediterranean country, was one where everywhere was very child friendly. But, they were expected to behave courteously. So running around the play area fine, but not around tables for example. The owner would rustle up a small portion of a local dish my youngest particularly liked that was on the Meze menu but not the regular menu. He would appear with ice creams for the children. But unruliness... No way.
Children need to be taught how to behave in society. Not taking them places doesn't do that. Allowing them to misbehave in 'family friendly' places doesn't.
Some children do have additional needs. They need spaces as well. Misbehaviour by others doesn't help those children. It can even distress them.