Shrimp have a similar fight or flight reflex as crayfish. They quickly flick their tail which rapidly propels them through the water (backwards). Often, when they do this action in a net, it can cause them to be thrown from the net.
Because of the nature of their carapace, they take little or no damage, even if they fall from six feet onto concrete. Their mass is so small, and their exoskeleton flexible enough, that their bodies easily handle the impact. If, say a Mystery or Apple snail took the same fall, their shell would most likely crack, or worse. That's due to the fact that, unlike the carapace of a shrimp, there is no give. So be glad that snails move at a snails pace.
Good luck!