We are talking about a bank robber with the cartoon outfit with big bags with dollar signs on them boarding the bus to and from the bank repeatedly. But he pays for the ticket so I guess it is fine in this proto-dystopian "late stage capitalism".

> We are talking about a bank robber with the cartoon outfit with big bags with dollar signs on them boarding the bus to and from the bank repeatedly.

Okay, let's proceed with your cartoon example.

The bank robber goes to the ticket machine, puts in money, gets a subway ticket, swipes the ticket through the turnstile and rides the subway. If the subway operator posted guards at all the entrances to the subway they could see the guy, but they don't, because that would be crazy expensive when they're not the police and their concern is just to make sure people pay the fare, and they can do that by installing automated floor-to-ceiling turnstiles that block entry to the subway unless you pay the fare.

Why is it the subway operator's obligation to investigate this crime, instead of the police? The subway operator could investigate it, the crime is happening in public view, but so could anyone else. Moreover, we don't want random common carriers to be denying service to innocent people based on scant evidence just for CYA purposes. We want penalties to be handed out in court once the prosecution has met their burden of proving the crime beyond a reasonable doubt.