Alternate, detatched delivery system

Someone recently posted on the Babyfit message board about what to tell people when they ask if you are breast feeding when you are pumping and giving a bottle. First - what a bizarre thing that anyone would ask you that in the first place (she said she was getting the question from total strangers - how wierd is that?!?!). So, I suggested she tell them she's using an alternate detatched delivery system with original source material :)