Why are some sons' answers different from what's written in the Torah?

Question

In the Hagada, the 4 sons ask questions (except, of course, for the son who doesn't know how to ask…), and they get answers. In most cases, both the questions and the answers are put in the form of verses from the Torah.

However, for the wise son and the evil son, the answer given in the Hagada isn't the answer given in the Torah for that question. (The naïve son's question and answer match, and of course the son who doesn't know how to ask doesn't have a question...)

The Wise son's question is taken from Dvarim 6:20:

כִּי-יִשְׁאָלְךָ בִנְךָ מָחָר, לֵאמֹר: מָה הָעֵדֹת, וְהַחֻקִּים וְהַמִּשְׁפָּטִים, אֲשֶׁר צִוָּה יְהוָה אֱלֹהֵינוּ, אֶתְכֶם.‏

and the answer given there is (translation of this - and the rest of the citations - is mine. Please feel free to edit if something isn't correct):

וְאָמַרְתָּ לְבִנְךָ, עֲבָדִים הָיִינוּ לְפַרְעֹה בְּמִצְרָיִם; וַיֹּצִיאֵנוּ יְהוָה מִמִּצְרַיִם, בְּיָד חֲזָקָה. וַיִּתֵּן יְהוָה אוֹתֹת וּמֹפְתִים גְּדֹלִים וְרָעִים בְּמִצְרַיִם, בְּפַרְעֹה וּבְכָל-בֵּיתוֹ--לְעֵינֵינוּ.‏
וְאוֹתָנוּ, הוֹצִיא מִשָּׁם--לְמַעַן, הָבִיא אֹתָנוּ, לָתֶת לָנוּ אֶת-הָאָרֶץ, אֲשֶׁר נִשְׁבַּע לַאֲבֹתֵינוּ.‏
וַיְצַוֵּנוּ יְהוָה, לַעֲשׂוֹת אֶת-כָּל-הַחֻקִּים הָאֵלֶּה, לְיִרְאָה, אֶת-יְהוָה אֱלֹהֵינוּ--לְטוֹב לָנוּ כָּל-הַיָּמִים, לְחַיֹּתֵנוּ כְּהַיּוֹם הַזֶּה
You should tell your son that we were slaves in Egypt, and G-d took us out using force and miracles, and He took us out of there in order to bring us to the Promised Land in order to follow all these rules and be G-d fearing, and that will be good for us.

However the answer given in the Hagada is

"אין מפטירין אחר הפסח אפיקומן" – we're not allowed to eat anything after the Pesah sacrifice except for a Matza that's called Afikoman

The Evil son's question is taken from Shmot 12:26,

וְהָיָה כִּי-יֹאמְרוּ אֲלֵיכֶם בְּנֵיכֶם מָה הָעֲבֹדָה הַזֹּאת לָכֶם.‏

and the answer that's given there is

וַאֲמַרְתֶּם זֶבַח-פֶּסַח הוּא לַיהוָה אֲשֶׁר פָּסַח עַל-בָּתֵּי בְנֵי-יִשְׂרָאֵל בְּמִצְרַיִם בְּנָגְפּוֹ אֶת-מִצְרַיִם וְאֶת-בָּתֵּינוּ הִצִּיל וַיִּקֹּד הָעָם וַיִּשְׁתַּחֲווּ
Tell him that this is a Pesah sacrifice for G-d because he skipped the Israeli's houses in Egypt when he hurt the Egyptian's

As opposed to the answer given in the Hagada which is from Shmot 13:8:

" בַּעֲבוּר זֶה, עָשָׂה יְהוָה לִי, בְּצֵאתִי, מִמִּצְרָיִם" – For this, G-d did for me when I left Egypt

So my question is: why doesn't the Hagada use the answer connected to the question, and instead provides an answer that either isn't written in the Torah, or is written somewhere else in the Torah?

Answer 1

In the Maharal From Prague's Hagada, he goes into detail regarding the 4 sons – why there are 4 sons; the reason each son's question is what it is – and then he explains the reason for the answers of each son. (Including, why the naïve's question and answer are the same as in the Torah.)

Since I couldn't find The Maharl's Hagada on the web, I typed up the part discussing the 4 sons, and uploaded it.

I'll bring here my translation of the part discussing the above question:

The Maharal explains that the answer given in the Torah to the wise son's question isn't the main answer. The wise son wants to know all the rules and Mitzvot in the Torah (העדות והחוקים והמשפטים אשר צוה ה'), and understand them properly. If we answer him about exile and redemption - he already knows about those. The real meaning of the answer in the Torah is to continue beyond ויצוונו ה' לעשות את כל החוקים האלה ליראה את ה'. And all those rules (את כל החוקים האלה) include all the Pesah Halachot until the last halacha – the afikoman, which is the last halacha of the eating of the Pesah sacrifice, and that's the meaning of the answer of the Hagada: teach the wise son all the Halachot till the last one.

As to the evil son – the evil son ridicules the Mitzvot (מה העבודה הזאת לכם). He doesn't understand the benefit of the "work", and therefore he doesn't want any part of it. And that's why it says "אף אתה" – you too. The same as he adds evil in not only not participating in the work, but also scorns those who do participate, you should add onto the answer given in the Torah and take the wind out of him by adding what’s written for the son who cannot ask and give him tit for tat – For me and not for him, to compliment what he said – for you and not for him. So that's the meaning of the words אף אתה – you should also add things that aren't written in the Torah's answer to evil son.