As for kennels and groomers, we've always had cats so I've never needed either (we have folks cat-sit for us). I can understand their concern about the spread of disease, but if they don't start asking more questions about what they're insisting on, they're going to be in as much hot water as the vets.
We had a TV report on this in Houston about 6 months back. It just scratched the surface but they interviewed vets, they intervied two vets, one who took one side one who took the other. With the information available to them, if they continue to insist on the pets getting yearly shots, they are only in business for the money and it's time to change vets.