Rehearsal Dinner

My daughters inlaws are being very difficult with the kids about the menu. They have decided they are planning the rehearsal not telling them anything and they should just be happy what they come up with. We are having the wedding catered and they want to use the same caterar and I put down my foot and said no as there menu does not fluctuate and we didn`t want the same items being served. They are saying they are going to have the main course be the same. What do you recommend we do? Ihave thought about just telling them that we would host the rehearsal our selves since I feel it needs to be the bride and grooms
Decision on what we have. It is there wedding! Let meknow what you think.
Thanks