Ben and Sally are married and have DC together. Ben has two DC from a previous relationship as well who live with them 50% of the week.
Sally's parents are well off and like to spoil their grandchildren. They are kind to Ben's other children but don't view them as their grandchildren nor do the children think of them as their grandparents.
Sally's parents like to take her DC out regularly, buy them treats etc etc. Same with Christmas and birthdays, they get LOTS from Sally's parents. Ben's children do as well but not as much as their grandchildren.
Ben has started suggesting this is unfair. For example, this half term Sally and Ben's joint DC have been / are planning to go out to various fun amusement places with Sally's parents but Ben's other DC haven't been invited and Sally and Ben can't really afford to take them themselves, they often come back from these places with treats from the gift shop.
Ben's other children have grandparents on their mothers side who treat them the same way as Sally's parents treat her DC so Sally doesn't see the problem. She doesn't believe it's her parents responsibility to pay for all DC to go to these places and she won't make her DC miss out by saying they can't go unless they all go. She also thinks it's fine for her parents to have a unique relationship with their grandchildren especially as her step children don't see them as their grandparents anyway.
Who's unreasonable?