Very good point. It's important to recognise that developers in many companies are often not fully aware of the intended use of features they're asked to create.

Another example that springs to mind is Uber, who used a tool called "Greyball" to avoid contact between drivers and authorities: https://www.reuters.com/article/uk-uber-greyball-idUKKBN16B0...

My initial reaction was astonishment that the engineers would happily implement this. And maybe that is what happened. But the alternative possibility is that product and senior management assigned different parts of the feature to different teams e.g. one team develops a pattern recognition system to detect users' professions, another team develops a spoofing system for use in demos, etc...