Dumb question?

I see videos of fish sucking in a bait and wonder do they sometimes suck in small pebbles on the bottom or pieces of wood or other stuff? Do they have a way to sort the food from the trash? Makes me wonder when jig fishing to they pick up the jig or suck it in?

The goldfish in my aquarium will suck rocks up on purpose. The seem to filter whatever is attached and then spit them out. Im sure gamefish will do the same.
DT

I’ve found lots of gravel in trout.