You'll need to read more than just that part. Many cities were accused of committing the sins of Sodom. The one thing you will notice is that while they are said to have committed the same sin, there is no mention of sex.
Even the use of "to know" does not mean that it was necessarily about sex. There are 914 confirmed cases where "to know" means literally that, to know something/someone. On the other hand there are less than 20 confirmed cases of "to know" meaning sex.
Even if we exclude the other cities that committed the same sin of inhospitality, there is no clear evidence that "to know" in the case of Sodom had anything to do with sex. The region was war torn and some strangers suddenly appear, so the town's men wanted to know them. Why are we supposed to automatically assume that means they wanted to fuck them?! It would make more sense that the town's men wanted to meet them and find out who they are. This makes even more sense when you consider that, in order to keep the men from attacking the strangers, Abraham offers up his daughters for sex if they will leave the men alone. Now why would a man offer his daughters up for sex to a bunch of gays?! That makes no sense.
Of the 5 cities {Sodom, Gomorrah, Admah, Zeboim and Bela—also called Zoar} that were destroyed that night, only Sodom is supposed to have been destroyed for homosexuality, yet they all committed the exact same sins. So why hasn't any of the other cities been labelled as fag cities?!