Any cleaning, including washroom, gets over in the morning. Nobody cleans the whole house. Everybody has specific areas. So, in the morning, they do their work and then they're free. Cooking 3 meals means, you do it three times a day. Which means you're working more than others. It's not about this work is less or that is less. It's that you realise how much a person is putting efforts and not just mock them saying kabza kar lia. Because good food, at least acc to me, is the most important. And if Shilpa is providing them that, putting extra efforts etc, that should be acknowledged and not mocked.
Hina khud kabhi bhi kisi ke liye extra nahi kar sakti. And while some people think that it's okay, why should she do extra, sab apna-apna karein, this shows a person's nature. Some may be okay with this and some may think that this shows she's not big-hearted. Personally, I think she shouldn't have mocked a person who was making extra efforts to provide good food in the house. Vacation pe nahi gaye hain toh kaam karne bhi nahi gaye hain. Har cheez se unki personality reflect hoti hai. And some more noble qualities of the Queen have been exposed through this whole house-chores division thing.