What does Rashi mean with "our Rabbis expounded what they expounded"?

Question

B"H

In Ester 1:7 when it mentions how the feast had different"vessels", Rashi gives his explanation, then finishes off "our Rabbis expounded what they expounded", a very peculiar language in Rashi.

שׁוֹנִים: מְשֻׁנִּים זֶה מִזֶּה, וְכֵן "וְדָתֵיהֶם שֹׁנוֹת". וְרַבּוֹתֵינוּ דָרְשׁוּ מַה שֶׁדָּרְשׁוּ:

Not only that, but Rashi is literally just translating the word שונים to mean what is simple meaning is, "different", then by saying "our Rabbis expounded what they expounded", it's seemingly implying that there are deeper meanings as well, but he doesn't mention them

Rashi could have simply said nothing at all in his comment, and the reader would know the simple meaning of the word שונים.

And if he's trying to exclude what one might think it means, seemingly he should have said specifically the difference between the simple meaning and a deeper meaning;

Often Rashi will say one thing, then afterwards add on, "But our Rabbis expounded...", And then he goes on to specify what exactly the Rabbis expounded, instead of just "our Rabbis expounded what they expounded", without any further explanation.

Not only does Rashi often do this, but in the very next comment on that same verse he follows this exact pattern:

וְיֵין מַלְכוּת רָב: הַרְבֵּה. וְרַבּוֹתֵינוּ אָמְרוּ: שֶׁהִשְׁקָה אוֹתָם כָּל אֶחָד וְאֶחָד יַיִן שֶׁהוּא זָקֵן מִמֶּנּוּ:

What did Rashi mean by this phrase? Is he trying to imply something else? To the best of my knowledge Rashi almost never mentions that specific language anywhere else, except for a few more times in the Book of Ester, like Ibid 2:5:

אִישׁ יְמִינִי: מִבִּנְיָמִין הָיָה, כַּךְ פְּשׁוּטוֹ. וְרַבּוֹתֵינוּ דָרְשׁוּ מַה שֶׁדָּרְשׁוּ:

And Ibid :9:

הָרְאֻיוֹת לָתֶת לָהּ: לְשָׁרְתָהּ, וְכֵן עוֹשִׂין לְכֻלָּן. וְרַבּוֹתֵינוּ דָרְשׁוּ מַה שֶּׁדָּרְשׁוּ:

And the same question would apply there, why tell us that the Rabbis expounded other meanings without telling us what those meanings are? He could just say nothing/stop after his own explanation.

Why did he say it?

Any references to commentaries or Sichos would help

Answer 1

Rashi famously only channels a specific kind of midrash, and will omit others if it doesn't also work well on a peshat level. He discusses this on Bereishit 3:8, with hearing Hashem walking in the garden:

וישמעו AND THEY HEARD — There are many Midrashic explanations and our Teachers have already collected them in their appropriate places in Genesis Rabbah and in other Midrashim. I, however, am only concerned with the plain sense of Scripture and with such Agadoth that explain the words of Scripture in a manner that fits in with them. וישמעו AND THEY HEARD — What did they hear? They heard the sound of the Holy One, blessed be He, as He walked in the garden (see Genesis Rabbah 19:12).

Note that Rashi doesn't mention the details of the many midrashim he is omitting.

Similarly, at the start of Beshalach (see my analysis of what is being omitted), that Hashem didn't take them derech eretz Plishtim ki karov hu, Rashi writes:

for it was near: and it was easy to return by that road to Egypt. There are also many aggadic midrashim [regarding this].

and does not mentioned what exactly these aggadic midrashim said.

Where Rashi does quote what the Sages say, this may well indicate that while he does not consider it the straightforward peshat, it is a midrash that operates well with the peshat and advances a peshat-oriented idea. So, saying that it was old wine, older that each person drinking it, advancing the idea of how splendorous the party was.

In terms of the two "shonot", the ideas are:

1. These were the Temple vessels, and a bat kol called out chastising them for using them "again", after the early ones were destroyed for using them. (See Megillah 12a.)
2. Their laws are different, in that they work to differentiate themselves from us. They won't eat our food, marry our women, or marry their women off to us. (See Megillah 13b.)

Apparently, these midrashim are too far removed from the peshat, or don't advance the singular peshat-derash thread that Rashi is trying to cultivate. He still mentions it exists, because that helps us know he is deviating what Chazal say, and that what Chazal say is midrashic.

Answer 2

He means there's a famous Midrash about it, but he doesn't necessarily see that as the simple explanation (or at least critical to the basic narrative). "What about the midrashic reading? Yeah, there's that too." In this case, as Shmosel graciously pointed out, Megillah 12a says that they were looted Temple vessels.

Another example would be Judges 16:21; the Philistines capture Samsons and make him "grind." Rashi says -- "working hard, grinding [wheat] at the millstone." And the Sages said ... what they said ... as the Talmud in Sotah reads "grind" in a um ... less-rated-G way.