What does the に in でしょうに mean?


Recently I was talking to a friend and the topic of credit cards came up. I
asked my friend (xx) if they had a credit card:

> ところで、xxはクレジットカードを持ってる？

and got the following response:

> そりゃあ持っているでしょう **に** 。

I'm not too sure what the に at the end means, but searching around the
internet it seems to be related to のに. However, sentences that end with のに
typically indicate disappointment/regret etc and I don't believe that was the
case here. I found [this](https://hinative.com/ja/questions/60469):

> あなた、それくらい分かっているでしょうに。 You know that, don't you? この場合の、don't you?
> に相当するのが、「でしょうに」です。

which seems close in meaning, but it doesn't feel like it's from のに. Any
elucidation on this would be helpful.




> 「そりゃあ持{も}っているでしょう **に** 。」

For the majority of native speakers, this is **not** a _regular_ ,
"calm/relaxed" way to say:

> "(Yes,) I have (a) credit card(s)."

That is why I asked above how exactly you asked your question that triggered
the use of the highly nuanced and possibly emotional に-ending.

My first impression when I read this question before the edit was that the
speaker was slightly irritated or surprised at your question -- " **Of course,
I have a credit card. Why would you even ask?** ". That could happen because
credit cards are far more common in Japan than what the popular J-vloggers on
YouTube seem to want you to believe.

According to
[goo辞書](https://dictionary.goo.ne.jp/thsrs/17288/meaning/m0u/%E3%82%88%E3%81%86%E3%81%AB/),
「（よ）うに」 does the following:

> ★後悔・不満・非難・疑問・感動などを表わす。

That means " **expressing regret, dissatisfaction, criticism, doubt, emotion,
etc** " and this is precisely why I said what I said at the beginning. Your
friend's reply is clearly nuanced. A regular, non-nuanced reply would have
been along the lines of:

> 「（ええ、）持ってますよ。」

The difference between that and the actual reply you received is huge.

What one could still not tell is exactly why s/he replied that way. To analyze
it, we might need to read the entire conversation that took place, which I
will not ask you to show us. As a native speaker, I could just almost hear the
silent 「なんでそんな（当たり前の）こと聞くの？」.




> 「そりゃあ持{も}っているでしょう **に** 。」

For the majority of native speakers, this is **not** a _regular_ ,
"calm/relaxed" way to say:

> "(Yes,) I have (a) credit card(s)."

That is why I asked above how exactly you asked your question that triggered
the use of the highly nuanced and possibly emotional に-ending.

My first impression when I read this question before the edit was that the
speaker was slightly irritated or surprised at your question -- " **Of course,
I have a credit card. Why would you even ask?** ". That could happen because
credit cards are far more common in Japan than what the popular J-vloggers on
YouTube seem to want you to believe.

According to
[goo辞書](https://dictionary.goo.ne.jp/thsrs/17288/meaning/m0u/%E3%82%88%E3%81%86%E3%81%AB/),
「（よ）うに」 does the following:

> ★後悔・不満・非難・疑問・感動などを表わす。

That means " **expressing regret, dissatisfaction, criticism, doubt, emotion,
etc** " and this is precisely why I said what I said at the beginning. Your
friend's reply is clearly nuanced. A regular, non-nuanced reply would have
been along the lines of:

> 「（ええ、）持ってますよ。」

The difference between that and the actual reply you received is huge.

What one could still not tell is exactly why s/he replied that way. To analyze
it, we might need to read the entire conversation that took place, which I
will not ask you to show us. As a native speaker, I could just almost hear the
silent 「なんでそんな（当たり前の）こと聞くの？」.

