No.
The money Nancy would make from painting at J.A.'s house would be used for the pedicures since it was extra money. However, since Brad didn't give her the weekly allowance, she wouldn't be able to do anything extra (implying she would have to use the $$ from painting for the regular household stuff that Brad would have covered).
Even so, if she felt like she was being controlled with money, you would think that any extra money she got would be hidden away for the times he didn't give her the money instead of spent on pedicures.