Haha well depends on the cat. Anyway, we shouldn't try to anthropomorphize behaviour of cats. They just do what they are designed to do by nature. We may consider some of their behaviour as "vengeful", but this is just projection of our cognitive concepts.

I already upvoted your post with 100%. Also feel free to advertize this project in any of your comments on my posts.
I shared this bitcoinstarter project in my Twitter too.