TBH, I think that would be the gift that would please Will and Kate the most. We have to remember that they also asked for donations to selected charities when they married. This is the kind of people William, Kate and Harry are and from the looks of things, even Baby Cambridge is getting into charity work and its not even born yet.
Personally, I think the Baby Cambridge Fundraiser is the greatest thing since sliced bread. There is such a flurry of attention given to this impending birth and what better way to put that attention to a good advantage than have folks make a donation for children that really need it.