Plenty of artists use photo references.
I know that Fate/stay night's backgrounds are traced from real locations (which was at least a step up from Tsukihime's "Google Image Search. Blur Filter. Done." approach).
For Negima, Ken Akamatsu copies real-life architecture for some things and uses 3D models as reference for others (he accurately depicts Welsh trains).
And I don't have insight into the workings of many professional artists, so I assume these aren't the only two places it's been done.
EDIT: http://en.wordpress.com/tag/real-life-anime-locations/