Ok so birds have an organ called a crop where they store food before digesting it. Which would make birdlike dragons more interesting if fantasy was written like horror science fiction. Imagine if after eating a village a birdlike dragon's stomach got full so it stores humans in it's crop instead. You're just sitting in a pile of chewed up guts and flesh and a few other people in a sack surrounded by muscles. Then after a few days you feel the walls pushing you into a hole into the stomach before being dissolved alive by acid.