respect should be mutual my friend. you respect their language, they will respect yours. include kannada names in delhi metro alongwith kannada announcements i am sure they wont have any objection on hindi boards and announcements in bangalore metro. now you will say kannada is not widely spoken in delhi. but hindi too is spoken by ony 3.41% percent people in bangalore and ranks 5th among the most widely spoken language behind kannada, tamil, telugu and urdu respectively.