Why share houses?

After a rewatch I was wondering why they shared houses like they did. When allie suggests it it sounds like it makes sense but given how we understand new ham it doesn't really. They say they need to conserve electricity and water but for whatever reason it seems like Phifer created the town with an abundance of those things. The impossibility of this abundance doesn't bother me it's a mystery show. But when they learn they have an abundance why do they still need to share? Especially as densely as they did I could see one to a room but 3?

I thought it might be a political move to increase safety and have more control over the residents and hit home the fact nobody owns anything anymore but this doesn't seem to be their intent.

Love this show but what gives?