E.J.
We are in the same situation. My parents have not liked my husband for many years and we've been together for 15 yrs. my husband knows that they don't like him and he doesn't like it when they want to come over or we go visit them. My parents tell me they are use to him and they see how well he treats me and my girls. I was so glad that when we moved back to Texas my father was working in Kuwait and my mother was soon to follow cause that would less stress on us. My kids hardly see my parents so to my kids it is not a big deal yet at least they haven't mentioned anything about it.
Also his parents do not like me either so I know how he feels. If they decide to drive through on their way to see their nicer son and wonderful daughter in law in San Antonio I often leave the house so they can see the girls. I don't like leaving my house so they can see the kids but that is only way to "make everyone happy" as my husband tells me. It doesn't make me happy leaving my girls even though they are with their dad. It makes me mad and my oldest starting to question why I have to leave. I have tried staying but they end up calling me names and saying horrible stuff about me that it always ends up in a fight.
So no I don't think granparents are needed in childrens lives, but it would be nice if they all got along to make life easier for everyone.