Sounds like what many people (perhaps your wife is one of them) subconsciously prefer and tend to, which as I've been informed on HN before (I am one of them, I'm aware I have such a preference but it's not consciously deliberate) is Zen's 'command position'.
I believe it came up before in the context of office desk arrangements. In office or restaurant, wherever, I find it very uncomfortable to have things going on behind me.