I htink this is quite common though fio
a friend of mine saw pc june ackland form the Bill in london a nd knew she knew her, thought she may be a colleague and said hi!
only realsied on the way home she didnt know her!
also a BIG friend of mine was having tea att he ritz and saw charlotte from SATC and said in her strongest black counrty voice " oh hello" thinking she too was someone she knew!
the shame