Maybe not bought but we rented a house where the owner padlocked 2 bedrooms shut and said if we wanted to use them it was an extra $200 a month to use them as home offices.
That's......beyond dumb. Like, if you don't pay him the extra $200, he's not extracting any extra value from these bedrooms. It's not like they can be rented to someone else in the meantime. So.....why do it in the first place?
A bit weird but there's at least an argument that there's some wear and tear associated with using the rooms and, presumably, the landlord thought that the slightly cheaper/smaller apartment--with a possible upsell--was more rentable.
He's definitely losing something. Property taxes are based on area and number of rooms. They could have found a tenant looking for the right number of rooms in their budget.