Not a pitting, because I just found this hysterically funny:
:smack: Of course!! books plane ticket Anyone got a spare bed for the night?
That’d make me chuckle, after the initial “WTF??” 
Wow. That’s an Instant Classic.
(but how do they know? Big list of US IP addresses? The domain name of the would-be viewer wouldn’t necessarily say, especially if it was a .com domain.)
Probably a reverse lookup of IP addresses: they’re registered to particular owners, and their location is a public record.
Yes, a reverse DNS on my IP does place me in the UK. As does the en-gb setting in my browser, I suppose.
Not sure how to get to one of these screens, but you may be able to circumvent it by disabling your referrer.