Why did Lot make a 'Mishteh' for his guests, whereas Avraham did not?
Seforno: 'Mishteh,' by definition, means that wine was served, and Lot was fond of wine, as we know. Avraham, on the other hand, served wine at the weaning-party of Yitzchak, which was attended by the leaders of the generation. 1
Moshav Zekenim: Guests who arrive at night are thirsty from traveling, so Lot gave them to drink before eating. Guests who arrive in the morning are hungry, for they did not eat yet, so Avraham gave them to eat.
See Sotah 10a.
Why did Lot bake specifically Matzos?
This conforms to the opinion in Chazal that the angels visited Avraham on Pesach, since the angel informed Sarah that at this time the following year, she would bear a son (Refer to 17:26:1.1:1). According to the opinion that it was in Tishrei (refer to 18:10:2.2), perhaps it is because Matzah takes less time to make, so he could serve them promptly.
Chochmah u'Musar (Vol. 2, p. 371): This shows the greatness of Lot. He observed the Torah and perhaps publicized it also to his guests, as he had learned from Avraham. Refer to 13:8:2:2**.
QUESTIONS ON RASHI
Rashi writes that Lot baked Matzah, because it was Pesach. Why, then, did Avraham not ask Sarah to bake Matzos when the angels arrived at his house?
Sifsei Chachamim: Sarah made Matzah Ashirah (kneaded with fruit juice.
Moshav Zekenim: The Torah mentions "Matzos" only when talking about Lot, to indicate that he had Matzos (quarrels) with his wife (who opposed having guests).
