They thought about their nice nights out. I love my kids and would never put them in danger by leaving them on their own so I could have tapas.
Everyone says now that they would never have done this, but my children are only a few years older than Madeleine and we certainly used to do this on holidays.
We used to go on yachting holidays in Greece/Turkey - there would be about 10 families each on a yacht, and we'd sail to a different village each day.
We'd all moor our boats in the harbour, I'd make the dc something they liked for dinner around 6pm, and then put them to bed in their cabins on the boat while dh and I went for dinner with all the other adults at a restaurant on the harbour. The dc would get very grumpy if they were dragged along to the restaurant and it wasn't exactly possible to arrange a babysitter when we sailed to a new village everyday.
We'd never be more than a 3-4 minute walk away and would check on them frequently. And we'd leave the boat unlocked & the hatch open, because we obviously couldn't lock them in on a boat.
This would have been when they aged around 3 and 6.
I remember that dd1 - aged about 6 - once appeared at the restaurant where we were eating. Dh and I were very shocked to see her there, especially because you needed to put a board across from the boat to the marina in order to get off, and we hadn't left it down. When we asked her how she got off the boat she said "a man helped me." We didn't do it again after that.
Now, post-Madeleine McCann, I realise what shit parents we were being, but at the time I honestly couldn't see anything wrong with it.