Why stay in an appartment? Well loads of modern 4* Hotels are appartment hotels that offer all inclusive, Half board, just breakfast or no food at all. The rooms are cleaned daily with changes of bed linen and towels. Lots of people with children like to have a place to prepare small snacks during the day and a seperate room where the children can sleep at night ( not all children are kept up till midnight, even on holiday) and parents can relax after a busy day in a comfortable environment without disturbing the children.
I stayed in a 4* appartment hotel in Lanzarote last year, we had a large bedroom and large dining room/living room/kitchenette with a nice balcony. I could make a decent cup of coffee in the morning without waking my OH who was still asleep. Wereas in a hotel room I would have probably disturbed him. It certainly wasn't a busman's holiday.