Owning a building is expensive, obviously, and there are a whole host of things that cost money that you wouldn’t even think about. If it’s a tall building, then the elevator will need regular maintenance, for example, unless you want tenants stuck in it and having to call out the fire department.
This landlord has decided that the maintenance should be paid for by the tenants, but he didn’t want to add it to their bill. Instead, his novel solution is to charge people per elevator trip. $35 a month to use the elevator seems pretty steep to me. I can see a lot of people just using the stairs.