The Bible: Promoting Incest?

There is a section of the Bible (Genesis 19:30-36, to be exact), where a strange incident occurs. When breaking it down and examining it, it is clear that incest is occurring between Lot and his daughters. The passage goes something like this:

"And Lot...dwelt in the mountains, and his two daughters with him...the first born said to the younger...there is no man in the earth to come in unto us...Come, let us make our father drink wine, and we will lie with him, that we may preserve the seed of our father. And they made their father drink wine: and the firstborn went in and lay with her father, and he perceived not when she lay down, nor when she rose. And it came to pass on the morrow, the firstborn said, Behold, I lay yesternight with my father: let us make him drink wine this night also; and go thou in, and lie with him, that we may preserve the seed of our father."

Basically, Lot's daughters got him so drunk off of wine that he didn't even realize he was committing incest. Twice. I believe there are three ways this passage could be interpreted. 1) This passage is supposed to warn one of the dangers of alcohol. 2) This passage is supposed to warn of the wickedness of women. 3) This passage is advocating incest in times desperate times of solitude.

So, I guess my question is this: If the Bible preaches against such things as overindulgence in booze and incest, why do you think this passage was included in the Bible?