That's so sad. Poor spiders. I mean, I know it's part of nature and that's the way the wasps ensure their next generation survives, but even so, it's just so gruesome. Getting eaten alive from the inside, poor things. :(

I...think they pollinate some things? And since tobacco hornworms are actually huge agricultural pests, they actually get used as organic, chemical-free pest control for tomato farms, so they do have a purpose. So it's just that nature is yucky, really.