Oh for sure. I remember early on going to Competitive Obedience class with my pup and meeting a woman with a beautiful Irish Setter. When the dog greeted me I felt his soft coat and slyly assessed his muscles and paplated his ribs. I looked up at the woman and said: You raw feed!it took a while......now i just secretly smile......
and now i can 'tell' kibble fed dogs from raw fed dogs. the build is distinctive.
She looked quite startled for a moment and started to say "how do you know?" but she caught herself and laughed saying" "of course you know"! We became fast friends.
I've had similar things happen the other way around.
And "civilians" always ask why my guy looks so good.