Moved in with my daughter & her family now there's problems, need advise?

[The Mom]

I recently moved in with my daughter, her husband & 2 kids as I broke up with my partner and have nowhere else to go. I asked them if I could stay with them and as payment (I am not working) I would look after their baby girl age 17months and would take care of the housekeeping. But it may now seem as if I have become their maid as I do most of the cooking, cleaning washing and once a week I have to babysit as well. My daughter is now giving me grief saying that they cant afford certain things since I moved in as the amount of sugar, coffee, eggs etc. We use every month has more than doubled since I moved in. Although I sont see it this way as I use whatever in the house for the house only. Financially they are battling a bit. Also they say I should follow their rules concerning raising the kids and that I shouldn't interfere but sometimes They neglect their kids as they are selfish with their own time.
They go out alone every monday night and I feel that since they are battling a bit finacially, they can stop going out on this night instead of fighting with me about saving them money.
My daughters husband just sits around infront of the tele the whole evening and rarely helps out around the house, and my daughter does help out more but prefers that I do everything. She says that seeing that she's working the whole day, she shouldn't have to come home and still do cleaning or house chores and because I'm not working & contributing I should take care of that. Since I moved in my granddaughter no longer goes to preschool so I'm saving them that money but my daughter says I'm not saving her anything.
I dont always agree with their methods on child rearing and soemtimes feel they are a bit to extreme with the kids. the kids dont get hidings everyday, maybe once a week or so but they hardley spend quality time with their kids in the evenings. When I try and give them advise they tell me to stop interfering? What should I do, I dont want to fight with my daughter as the situation at home is becoming a bit tense. They blame me!
I divorced my husband when my daughter was 6 and my husband raised my kids.
I dont turn the kids against them. I would never do something like that. I just dont agree with the way they raise them sometimes.
My daughter keeps telling me that its her house, her kids and her life and that I should be the one to change seeing that i'm the onw imposing on their life.
My daughter keeps telling me that its her house, her kids and her life and that I should be the one to change seeing that i'm the one imposing on their life.