Boomer- we stayed there last year (got upgraded) and liked it so much we're going back this year for a longer stay. One thing I have noticed from reading these boards, is that if you have used another concierge service, you may find sugarloaf disappointing.
We've never stayed at the poly or AKL concierge (which by all accounts are amazing- lots of food offerings, dessert and cordials offered, a chef in the lounge), so we're pretty happy with what we get at GF. From what I remember, the breakfast is pretty extensive- I think you will really make up some of the extra money feeding your kids at this meal alone. There are cereals, oatmeal, lots of fresh fruit, juices, tea and coffee (here's a photo of my dh and dd in the lounge at breakfast). I think you also get a newspaper, but I'm not sure about that one.
They'll give you sodas and iced drinks in paper cups with a lid and a straw that you can take with you to the park. There are also cookies and brownies out most of the day and a huge bowl of fresh fruit - great to grab a couple of bananas or slices of melon for my young ones on the way out to the parks. We filled the kids insulated cups with iced lemonade or water and tossed them in the back of the stroller, so we never needed to stop and queue up for an overpriced soda while touring in the morning.
Another big bonus I found with lodge concierge was the afternoon tea. We were coming back from a morning in the park so that the kids could nap, and on passing through the main building, my mom spotted the afternoon tea being served. We both agreed that when the kids were settled, dh would look after them and we would head back for tea and scones. We checked out the menu and saw $25 a head and thought, hey, we're on vacation, why not? Imagine our surprise when we got back to the lodge to see the same food (scones, chocolate mousse, sandwiches and trifle) all laid out!! I know we didn't get the whole afternoon tea experience, but it was really nice to sit in the cool lounge and enjoy the break.
Anyway, sorry this is a bit long, we only stayed one night, but I was pretty impressed- feel free to ask any questions and I'll try to answer them for you. I think you'll really enjoy your stay!