I agree with Hobbs, try and gauge where the vet stands on cat nutrition. Some of them (it is rumored, lol) don’t just try to shove Hills & Royal Canin on to you.
It would be great if your vet was one of the more open-minded variety.
However, if your vet is old-school Hills/RC pusher - I don’t know if it’s worth even trying to get the point across that “thanks for your talk on Hills dry food, but I won’t be feeding it, I’ll be feeding Bozita/Grau/Almo wet foods with a small portion of Orijen dry every day”.
I tried this route with my own vet and to be honest I am sorry I did. It just created animosity. He felt I was disregarding his professional advice. I felt he was disregarding my opinion, experience and research. I eventually caved in and said “your right, you’re right, I’ll go back to Royal Canin dry food immediately, but I’ll be buying it from zooplus as it’s cheaper”. I just knew if I forced the issue… every time I turn up at the vets with anything he was going to write it off to “wrong diet, your fault, you created this problem”.
So although I thinking lying to a vet is a very stupid and irresponsible thing to do… it’s exactly what I am doing right now.

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And I have been lying to many vets for many years now about how I wean my foster kittens too… as most vets just want them weaned onto (for instance) Royal Canin Baby or Kitten dry food. Their theory is… if you give kittens wet food or raw food or cooked meats or boiled fish or raw meats and fish, you create fussy eaters kittens who then create problems for the shelter as new owners complain they won’t eat the dry food. I try to expose my foster kittens to as much different food stuffs as possible (including dry kibble) and will continue to do so. But to “keep the peace” I just lie and say “of course all they get is Royal Canin baby/kitten kibble”. But I always get compliments on how well my kittens look, how I never have underweight kittens, lol, go figure.