I would drop ALL magpies given the chance, and carrions. Larsens are the way to go though if you want to really help the local wild bird population. I have taken 38 magpies and 92 crows this year.
We dont extend any courtesy to rabbits that probably have young underground, or pigeons mullering crops. I will put 54g through the nest if I know where it is though.
If your magpie is feeding chicks then it will be feeding them on other birds young and eggs for sure. Do what you feel comfortable with