Rspect your opinion. But so far we have not seen the whole truth of RK's past. What happened to hsi da, what makes his mother to remaryy that also someone like Bhatia, and lot more. So it is too soon to judge on this. I am sure CV's won't disclose everything so soon and let viewers know what was RK's past. It is only been about 80 episodes and still lot of traacks are at builduip stage.
If we look into how much time has passed in the show not as one day as per an episode, then not many days has passed. Maybe close to 2 months. People go abroad for so many days. His mother is someone who always obeys his step dad. So even if she comes to know about the jail thing, he might have convinced it is of no use, since RK hates her mother, there is nothing they can do and Bittuji will handle it like he always do. That is what they are doing even now. Letting Bittuji handle everything, even when they are near to him and living with him.
RK is not living with his mother or step dad and brother. Infact they are lving with him and using his money here. He is taking care of all of them financially. They all are dependent on him. So there is no reason for him to live anywhere when it is his own home.
I have seen some stars mom dress like RK's mom. Like Sonakshi Sinha's mom too sometimes wear saaris and lot of jewelleries and even stars like Vidya Balan and some others wear traditional saaris some time. And it is not that RK introduces his mother to the public saying she is his mother and so and so and neither he is giving her a chance to be his mother. So she is not living a Super Star's mother's life. She is just a normal person who stays at home.
Whethere Super star's mom or a normal person's mom, for mothers their daughters and sons will always be their son and daughter not a Super star. So RK's mom cooking for him should not be taken as an unusual thing.