Your birds are your responsibility, no one elses. You have the right to take care of them anyway you see fit, be it right or wrong. It's your thing. The rest of us will take care of our birds as we see fit as well. I have read post on BYC where people have lost some or all of their chicks because they used cedar shavings. I have done the research myself and would never consider using them for babies, ever. I am glad you have never had a problem and hope you continue to have the luck you have had up to now.
I don't quite get the 'over medicated' statement you've made in your posting. Are you referring to the Amprolium? Have you ever bothered to look into what the medications are for and how they work inside the body? Really, I don't understand. would you explain what you mean?
The feed normally given to chicks has the proper amount of protien in it already and to say that cat food or anything else should be given is false. The only time I have ever used cat food, canned, was when I had a picking problem with chicks and it was in desperation. I used 2 small cans of a fish based cat food between 35 chicks over 2 days. The picking stopped and never resumed. I would never think to offer my birds canned or dry cat food as a supplement. As has been pointed out by Michael Apple, it isn't good for them. Not just the salt and calcium, but the protien as well. It's way too high for their needs. Medicinal, as I used it? Yes, I would do it again if everything else failed to work and only for the problem of picking.
Sometimes we take chances with our own charges, birds, whether out of desperation or ignorance. Sometimes we get lucky and sometimes not so much. We all have opinions on what we think is right, but there are tried and true methods that have shown themselves to be the 'right' way of handling certain situations. I urge everyone to do the research on all of the possibilities and the tried and true as well and make their own decisions.
