The cruise line is family friendly; therefore, all of the restaurants are open to kids. End of story!!
Parents shouldn't feel guilty taking their kids with them to any venue that is part of their vacation package. I say this as someone with no children. I just get sick of people complaining that there are kids acting like kids on a kid friendly vacation. Would you also complain that there are kids at Disney World?
The kids are passengers, just like the adults. If you don't like kids, go on an adult only cruise, please!