The sad thing about this technology is that it's routinely used, as enumerated in this article, to a completely worthless end. Cocaine should not be illegal anywhere, nor should surveillance stings be set up to entrap people.
You used the word "entrap". I don't think it means what you think it means.
Setting up surveillance of people doing what they independently decide to do on their own, is not entrapment.
Entrapment is when you interact with a target and actively convince them and/or enable them to do a criminal act that they (arguably) would not have done on their own without your prompting/enabling actions.
All of this money and effort just to continue to prosecute a meaningless and harmful "drug war."
At this point, countries are literally spending money to prevent themselves from making money (by setting up legal markets and tax structures).
It's all so absolutely and miserably asinine.