Social construct.

[paulpablo]

And I'm saying pets are a social construct. It depends on the outlook of what people agree on socially.

You just said to ask your wife about the spiders.
If I did and she said yeh they are our pets my husband is talking shit, and if you and your wife were to specifically chose to pay attention and care for one of those spiders and call it Sidney then that spider that isn't a pet would now be your pet spider.
In reality your wife doesn't want them as pets so they aren't.

You point out one difference between a pet spider and a wild spider, right there.  The care and feeding thereof.  Another would be their containment. 

  Even in the exception seeking subset of wild caught animals kept as pets, you'll still find genetic divergence between wild populations and captive animals, changes to behavior, and objective differences in situations and circumstances.   

No I'm not saying it's a pet spider because it's contained or cared for. This is what makes pets a human construct.

You can take your pet out of it's containment and it's still your pet because you think it is. Caring for an animal doesn't define a pet because people neglect and mistreat their pets. People let their cats out of the house sometimes I knew a family that let their rabbit walk the streets for some reason.

You won't find genetic divergence between a spider in the wild and a spider that was in the wild and spent 1 second in a human created containment.

There might be a genetic divergence after spending a long time in a cage at which point a human decides whether or not to call it wild or domesticated or not.