Many were very young. It was a very "Oliver twist/artful dodger" kind of thing. it was a team put together by the one adult woman who also died in the hotel room (they say her name a few times, like "I was doing a job for Claire" or "I never would have bet it'd be YOU that left Claire's team", I just don't remember if her name was actually Claire, lol) that she had essentially filled with smart, disadvantaged teens, to come do spy stuff for her. Amy definitely had no regard for rule of law, and had been raised to be selfish, except in the case if her team. She'd also clearly worked with the team on other things before. Amy had likely done things that left people extorted or dead in her and her team's wake. She just never had to witness the consequences, so may not have realised how terrible the stuff she was doing actually was.