The text is within the context of a time and place with certain general customs and assumption.
First, it needs to be said, that the text does not actually tell us one way or the other whether Lot's own intended action was good or bad (it merely describes what Lot tried to do, without assigning moral quality to it).
Moving from that into the actual situation the text describes:
Hospitality, the welcoming of strangers, was a supreme virtue in the ancient near-eastern world. And Genesis describes two episodes as parallels/contrasts to highly the marked difference between Abraham and the Hebrews with the surrounding nations.
Note that prior to the whole ordeal with Sodom, Lot, etc the text talks about three angelic visitors coming to Abraham. Abraham welcomes them, he prepares a sumptuous feast for them.
Following this angelic visitors go into Sodom, and in stark contrast to Abraham and his people's hospitality, these visitors are greeted only by an angry, hostile mob.
Further, let's keep in mind that Genesis is part of the Torah, the five books of Moses, and additionally it is a prologue to the Exodus and God making a covenant with the Israelites. These two stories establish a parallel contrast, with Abraham as Patriarch of the Hebrews, father of Israel, he represents here what is expected of God's people. And, indeed, God established commandments specifically for Israel for the right and just treatment of foreigners and strangers. Hospitality was to be a prime virtue of God's People.
In this context, the text describes Lot trying to bargain for the visitors. While it seems barbaric and misogynistic today, in those days a man's daughters were his property, and thus Lot is bargaining, offering what is his (his own flesh and blood daughters) to try and save the visitors. Now we can look at that from our perspective and make many a moral judgment; but the text must be read from within the context of time and culture.
But this is the context of what is described in the text, it is part of a larger narrative teaching the essential importance of hospitality and how that would be a marked distinctive of God's people in contrast to those people, who in their wickedness, mistreat neighbor and stranger; whereas God's people are to welcome, feed, clothe, and nourish the stranger.
In fact, in the Prophet Ezekiel, we find Sodom as the archetype of a people who mistreated the poor and the oppressed, who did not welcome in strangers. It is also in this context that when Jesus sends His apostles out, He says concerning those who will reject them that it will be far better for Sodom on Judgment day. Sodom's mistreatment of the poor, the stranger, and the needy is the chief sin of the city, and the reason why it was destroyed (at least according to the Bible itself).
-CryptoLutheran