hold over head

I have noticed that people with young children in their family tend to use there children as bait. My parents have two children and it seems that my sister with her kids usually take president. I also noticed this more so with my wife's brother and his children. It seems that since they have children they can do as they please, meaning that if dinner is at 5 they can say well the kids, blah blah blah kids.. and dinner will be at 2.

For the past 7 years we have always done Christmas at my wife's parents house. We wake up early (wife can sleep till 3m ) 10 to her is early ! We would wake up early and her brothers family would come over early and we would have a brunch. My FIL is an amazing cook AMAZING! So we eat chill and then when we are stuffed to the gills we do presents under the tree and then stocking stuffers. It was fun and warming. After our time we would go hang out with my wife's second family .

Well ever since last year my BIL and his wife has changed things around. Quite frankly it sucks. He changed it all around because now he has kids and well his wife's family is divorced ergo she has to attend 2 Christmas's with her family and she does not seem to have much regard for his family and well we ( my wife and I) have to take the back seat or so it seems. The kids need to nap or we wanna do our own tradition at out house... which I get but you wake up at 5am to do Christmas at your house (or that's what you say ) and well you cant drive 30min to your Husbands family's House like you did every year prior and do brunch and Christmas with his family ! Because what happened is my MIL and FIL end up going to there house to see the kids (my wife and I just sit and have to wait for everyone!)
You'll be back home by 2 and your children which you Taunt the grandparents with can finally nap!

Its not like we live right around the corner anymore we are traveling from 4hrs away but we don't have a child yet to use as a pawn to get our way and manipulate the situations.

I just don't get that. Why do parents who become Grandparents send there kids who dont have children to the back of the bus.