I agree. Some Betta fish are known to eat shrimp. But not all of them. I have one Betta that won't touch them, but he isn't to fond of Cory cats.
Bettas: Rose, Sophia, Addie, Ghost, Buster, Holt, Aidan, and Mercutio!
Just my animals: 0.2 Cornsnakes, 0.2 Bearded Dragons, 1.0 Water Dragon, 2.2 Crested Geckos, 1.0 Tiger Salamander, 0.0.1 Tadpole, 0.0.2 Red Eared Slider Turtles, 0.0.1 Map Turtle, 0.0.2 Hermit Crabs, 1.0 Hamster, 1.0 Rabbit, 0.1 Horses, 2.2 Dogs, 0.2 Cats, Chickens, Ducks, Oscar Tank, Planted Bowl, 10 Gallon, 4x 0.5 Gallon, 5 Gallon, and Planted 25 Gallon Tank....Is that it?