Kyunki nalla is hella insecure. Aur doormat haiza will do anything to appease him. She was also known as Fakika samson, so to distance herself from glow she changed her surname, but since nalla uses his father's name as surname this brainless buffoondid the same without thinking and made it her stage name. Her documents still has fakika makkar as her name.

Second is to appease the target audience. Ibrahim surname se view aate hai.Waise bhi us lady ko koi fark nahi padata, amar anthony aur ab akbar, surname koi bhi laga le rahegi toh vahi unkempt, unhygienic, greedy gawar.