I can understand why this is a bit hurtful, OP, they live 10 minutes away, but are disinterested in spending time with you, asking about your family or coming around to look after the kids, despite being late 50s and not limited by age.
They aren't going to change, it is sad, but it is what it is.
I don't hear any entitlement here- the Op is sad because the grandparents have no interest in her family whatsoever, and they are close enough that there are no easy excuses to why that's the case. They just aren't interested in the whole thing.
Your husband is either a bit emotionally illiterate himself, asking them to babysit when they never ever volunteer, or he's just protecting himself by telling himself they are not that bad.
To those saying this is normal, I don't think it is at all and don't know any grandparents like this at all. All relationships are usually built out of bonding and joint activities, reciprocal caring and interest in each other- if you don't have any of that, you don't have a relationship.
It won't change though OP and I think just not putting yourself out for them to get rejected is the way forward, if they come for a cuppa, have one and leave it at that.