I eat a lot of protein in its natural form without a problem, including the higher collagen cuts of beef and lamb, the slow cook cuts and ones that include bone marrow. Like you, I'm not keen on seafood and rarely eat it.

What makes hydrolysed collagen in supplements foreign is that they've been processed/hydrolysed to break collagen into smaller fragments before you take it. Natural collagen in food arrives in the body as complete collagen in a recognised form, along with the food which naturally contains it.