I can only speak of my own experience here in Switzerland. But nobody minds if a corner of the park is a little more busy as long as everyone is nice to each other. You don't consume where you buy so there is nothing really not kid friendly about it. Also parks where this things happen are usually not exactly tiny playgrounds but actual parks.

FWIW, at one point I had my bike locked up in Hamburg, and had lost my key. I still had the key to the (small) chain I brought with me, but not the key. When I was fussing around my bike - I no longer recall exactly what I was trying to do - the local drug dealer actually came over to question what I was doing :)

(In the end I got a new lockset installed on the bike, cost 750 EUR, involved replacing the ignition, the fuel cap and the rear seat lock, only only happened because I brought my registration documents with me on the trip. The bike, at that age and mileage, was only worth about 3000 EUR, to put that in perspective. But the point of the story is a criminal challenging potential criminal activity...)