I've always had a love-hate relationship with the Haight. Some of my favourite shops and restaurants are there, but due to constant social interference it is not a fun place for an introvert to visit for very long.
One of the starkest contrasts between the US and the UK I have noticed this trip is this level of social interference. On a normal day walking down the street in Edinburgh, the only social interactions occur with people I know or tourists needing help. (Sadly, tourists think I look like I know where things are.) Most everyone walks briskly, with purpose, and takes up very little space.
I've lived in other US cities before, so I know this is not specific to San Francisco, and certainly varies by neighbourhood and event. But the Haight has a particular density to it, and lots of people just hang out in clumps or wander without much awareness of other people. I noticed this as much inside American Apparel and Whole Foods as I did outside on Haight Street itself.
I got over my introverted twitching enough to enjoy a giant salad in the company of FunkyPlaid and many tiny birds.