这个句子中的 as to 怎样理解？谢谢！

I realized that the villagers who had gathered around me were arguing as to who should have the honour of receiving me as a guest in their house.

这是高考语法填空中的一个句子。句子的意思并不难理解。

我的问题是：如果没有这个as to, 似乎这个句子就很容易理解。那么 as to 是什么意思呢？或者它在结构上有什么意义呢？谢谢！