How many URLs, as a percent of all browser navigation, do you think are typed by hand? And I don't mean "news.ycombinator.com", I mean the full URL, like "
https://news.ycombinator.com/news".
And in those rare cases, of course you can collect strings from the user. But then they have to be parsed, and that's what should be on the wire. IP addresses are also sometimes entered by hand, but we don't send those strings in TCP packets.
