Does the child "ask" you for food? I find some people just don't know what to do with kids so food is an easy way to keep the busy and happy. Maybe they feed him 7x a day just out of habit and assume he NEEDS the more frequent feedings so worry he will be hungry at your place?

We've made a habit of only feeding my daughter (and DCK) at the kitchen table. It is more effort to have a snack than it is to otherwise occupy a child. I ave many friends that literally throw fish crackers and fresh berries on the coffee table for the kids to eat while playing. I think it prevents children from recognizing the feeling of being hungry and needing nourishment over just eating because it is in reach.

The main question here is do you feel this child NEEDS more food and are you willing to change your regular routine to do this. If not, tell them and they can change daycares or adapt.