Reminds me a bit of this woman who was 'spiking' vegans in her restaurant.
I can only guess at the kind of abusive childhood that conditions a person for such corrupt behaviour as an adult: https://www.theguardian.com/lifeandstyle/2018/jan/03/head-chef-gets-death-threats-over-spiking-vegan-food-claim
Fortunately she was backlashed to pieces and her reign of vegan-spiking is over, for now.
Yes, I read about her. A wretched woman.