The whole “how the hell does this predatory creature get enough sustenance” thing that plagues fantasy and sci-fi occasionally gets so absurd it loops around into being funny, like the scene in Star Wars when the Millenium Falcon is flying through an asteroid field and gets swallowed by a worm.
I could complain about that, but I could also conclude that the supply of reckless space pilots flying into asteroid fields has been consistent enough for the past few million years for animals to evolve to prey upon them.