Dear Sana88,
I don't think wearing a kurta with a chudidaar or a salwar without dupatta looks vulgar. As per me there is no vulgarity in this kinda dressing until and unless ur attire is not revealing or exposing. Now, you will also say that girls should wear dupatta with jeans and t-shirt. Whats the harm if a female can carry trousers, jeans, shirts professionally then she can also carry salwar suit decently without wearing dupatta, which does not make any good rather it just creates hassle during work.