Brachos 6b: Failure to return a greeting as גְּזֵלַת הֶעָנִי

Consider the following gemara from today's daf, Brachos 6b:

וא"ר חלבו אמר רב הונא כל שיודע בחברו שהוא רגיל ליתן לו שלום יקדים לו שלום שנאמר (תהלים לד, טו) בקש שלום ורדפהו ואם נתן לו ולא החזיר נקרא גזלן שנאמר (ישעיהו ג, יד) ואתם בערתם הכרם גזלת העני בבתיכם:

Or, in English:

R. Helbo further said in the name of R. Huna: If one knows that his friend is used to greet him, let him greet him first.³⁸  For it is said: Seek peace and pursue it.³⁹  And if his friend greets him and he does not return the greeting he is called a robber. For it is said: It is ye that have eaten up the vineyard; the spoil of the poor is in your houses.⁴⁰

How shall we understand the latter prooftext? That is, we want to prove that if one does not return a greeting, one is called a robber, because of (Yeshaya 3:14):

יד  ה בְּמִשְׁפָּט יָבוֹא, עִם-זִקְנֵי עַמּוֹ וְשָׂרָיו; וְאַתֶּם בִּעַרְתֶּם הַכֶּרֶם, גְּזֵלַת הֶעָנִי בְּבָתֵּיכֶם.

14 The LORD will enter into judgment with the elders of His people, and the princes thereof: 'It is ye that have eaten up the vineyard; the spoil of the poor is in your houses;

But this pasuk only speaks of robbing the poor, rather than not returning a greeting?

Rashi explains (on the daf):

גזלת העני - והלא אף גזלת העשיר גזלה היא אלא גזלת העני שאין לו כלום לגזול ממנו אלא שלא להשיב על שלומו:

"The robbery of the poor -- and is not the robbery of the wealthy also robbery ? Rather, robbery of the poor who has nothing to rob from him, except that you don't return his greeting."

In other words, it refers to robbery of a response to a greeting because a poor man can only be robbed of this.

This seems quite far-fetched to me. Rather, I think it is a simple derasha on the word הֶעָנִי. This is not from the language of 'pauper'. Rather, it is from the language of 'response'. So גְּזֵלַת הֶעָנִי means 'theft of the response'. For instance, in I Shmuel 9:

ח  וַיֹּסֶף הַנַּעַר, לַעֲנוֹת אֶת-שָׁאוּל, וַיֹּאמֶר, הִנֵּה נִמְצָא בְיָדִי רֶבַע שֶׁקֶל כָּסֶף; וְנָתַתִּי לְאִישׁ הָאֱלֹהִים, וְהִגִּיד לָנוּ אֶת-דַּרְכֵּנוּ.

8 And the servant answered Saul again, and said: 'Behold, I have in my hand the fourth part of a shekel of silver, that will I give to the man of God, to tell us our way.'--

And we should not try to force it into the peshat meaning of the pasuk in Yeshaya.

Related, BTW, is the phenomenon in some communities of people not greeting fellow Jews with a Good Shabbos, or looking at them strangely rather than returning said greeting. See here:



And here.