In the Cretaceous period, the sanitary conditions here were abnormally backward.
And what bacteria were present, what viruses were carried in the organisms, and what kind of harm these viruses could bring to humans.
They did not know yet.
Even in modern society, in an ERA of advanced medical technology, there were still some viruses that humans could not deal with, not to mention that it was tens of millions of years ago in the Cretaceous period. It was possible that a slight infection with a virus could leave all humans helpless and waiting for death to come.
Not to mention creatures like pterosaurs. Pterosaurs looked like lizards, and it was well known that lizards carried a lot of viruses. Therefore, even if they were cooked, they didn't dare to eat it.
They brought food from the modern world before they came through the folded space, specifically food fit for human consumption.