Yeah this has always gone on. Early in my career a raving customer called up and burned my ear asking why his site wasn't up. "You're the web guy, this is what I'm paying you for . . . " Turns out his address bar was hidden (probably from browsing pron) and he was using the search box from his MSN "home" page. The site was two weeks old and hadn't been indexed. :-\
Yeah, my top ranked search term is my address many months. I'm guilty of cuing an address a number of times using the address field memory, because I'm too lazy to bookmark... but never actually by searching. Kind of bizarre.