Admittedly, the spider will have to either eat live insects or die. I think what really surprises me is the psychological compartmentalization of: This is charismatic megafauna and I would never hurt it and whosacutlittlepuppy? v. It’s just an insect, let’s capture it and feed it to a predator for fun.
I’m not blaming anyone here, ultimately there isn’t a whole world of difference between actively feeding a spider and just letting it live in your shop, catching prey on its own. But some curious behavioral switch seems to flip here.