I seriously doubt that the FaceMash guy was planning mass surveillance from day one. The people who propped him up might have, though.

Wrong. He literally made fun of users for giving information that he could use to spy on them and share that ability with friends. It was a childish form of spying but the intent was there and the monetization tactic came later.

FaceMash is a very primitive example of mass surveillance and data gathering: use people's pictures without their consent, collect the social rankings in a database somewhere.