To be honest, not a lot, they only let you past the building door. So as a thief, I can: A. Scrub through a hypothetical leak of all that data, or B. Tailgate someone (even in security-conscious buildings this isn't much harder than following someone while carrying a box in both hands)

Locks are for honest people.

Until you live in an apartment complex that has eliminated keys. My place is all keyfobs (except for the mailbox).

So it can be used to steal or deliver packages.

Letting people get into the locker room or bike room can create issues.

You can get a great lock, but what they lock into is usually a very weak link.