A prime example of what you're talking about is apartments around military bases; landlords know that everyone on the base has to stay in the area for at least

A prime example of what you're talking about is apartments around military bases; landlords know that everyone on the base has to stay in the area for at least a few years, so they did sketchy stuff with what they'd charge for rent because they knew that the person couldn't leave. The pay rate of different ranks is public information, so if landlords found out you got promoted, they would raise your rent by difference between your old pay rate and new pay rate. Eventually the govt had to step in and make it illegal to charge different rent amounts based on what the service members rank was.