Why does he use "we" here?
Native speaker’s answer
Rebecca
The pronoun "we" is used here because he is referring to what is in front of both himself and the other guy in the room. However, the expression "what do we have here" is a common expression that is used when someone finds something interesting, surprising, or something which are curious about. "We" is always used in this expression no matter who is in the room, although the expression is usually said when there is someone else in the room and so it can make sense to use "we". Ex: Well well well, what do we have here?