If you want to then do it. I understand why people may want to eat out for every meal but we prefer to have some kind of kitchen, however basic.There are plenty of good reasons to do a bit of cooking.
Someone in the group who is vegetarian, or who has a food allergy.
Cost. Lunch and dinner with adult sized teens is expensive. Money wasted on a young child who decides they're not hungry or too distracted that holiday. When one of mine was 3 he would only eat dry bread, yogurt and fruit for a week. It was easier most days to feed him that in the apartment and let him play whilst we eat.
The stress of taking a young child out could be less than the stress of a bit of washing up. They may be perfectly well behaved in a restaurant but it's hardly a relaxing meal with a second bottle of wine territory.
If you've had a full day sight seeing and have eaten out at lunch, it can be nice to collapse and prepare a very simple meal. Rather than get cleaned up, nicely dressed and hunt for somewhere. We have two city breaks planned this year with kids and have apartments booked for both for the above reason. Interesting meal out at lunch, something thrown in oven in the evening.
However nice the resstaurants you find it is very hard to have any kind of normal diet eating out all the time. There's not many places that fill half your plate with veg and a small portion of carbs. After a few days I crave a huge bowl veggie curry and chillies.