Mind The Barrier
Typically when you have a barrier set up, it’s supposed to one thing: prevent people from getting in where they’re not supposed to. Or in this case, you just do whatever you want. Chalk it up to laziness? Possibly.
New Species Discovered
While we might not be experts on all animal species, this is plainly animals 101. When a package says “tarantula” then one should expect the eight-legged creep, and not a cockroach. Although it’s equally creepy, it’s not what the package is selling. So it’s also marketing 101 we suppose.