I have to echo what someone said upthread--people will ask a pregnant woman anything!!!! It's unreal.

2 girls I work with just had babies--one September 27, and one this past Sunday--neither of them are breastfeeding, and it never even crossed my mind to even ask them why, or try to convince them to.

I guess people will always continue to be nosy, and rude, and you just have to do what you can.