So one of the character wonders about the relationship between the two people and asks character B this: "Would you come this far when you are only shopkeeper and client"?
The answer seems to be "Those kind of things also happen. After all, right now he has a lot of friends (phrasing). However how is なんて here being used?
The usage doesn't sound correct to me. なんせ makes more sense but that's still odd (because it ends with かな but なんせ implies the speaker knows it to be true, so it sounds odd).
Maybe it was a mistake by the author? Maybe something got replaced and なんせ was forgotten to be changed.
The basic meaning of なんて is explained here: Why does なんてね mean "Just kidding"?
Specifically in this context, this なんて indicates "客と店員がこんなところまで来ますか" was a question said half-jokingly to baffle the listener. That is, he asked it even though he did know that a shopkeeper and a client might well visit that place. I think "Just kidding" is an okay translation.
