So, in the UK we have a thing called the “Bedroom Tax”. If you live in a council house/are a housing association tenant, have a spare room, and receive housing benefit, you can receive less housing benefit for having a spare room. It may be a way for the government to disincentivise people living in council houses too big for them, which may build more houses.
Therefore, should you pay more tax if you have a spare bedroom and own your own home? It could be income tax/council tax, and a way for the government to raise funds to build more houses, and may encourage people to let out their spare room.
You can argue for your own country to/to not introduce this.