I guess there's always likely to be some arse who has to make a comment, rather than just seeing your baby for the special, perfect being he or she is. When my daughter was newborn (8 lb 15 oz), everyone commented on how long and big and strong she was, then she gradually dropped nearly three centiles (normal 'catch-down' growth apparently, but it still terrified me). When she was about five months, a checkout lady in ASDA asked me how old she was and when I told her, she was all like 'Ooh, really? But she's TINY!' She wasn't tiny. She was following the 50th centile line, so completely average - but her comment scared me so much that I went straight to the HV to get her weighed and asked her if my daughter looked normal for a five month old.
I too feel self-conscious BFing in public, because babies are such an area of interest to every nosy sod out there, and wherever you are/whatever you're doing with your baby, there's always going to be someone having a sneaky, or all-out obvious, look. But we don't have to explain anything to anyone. Regular adults in restaurants or checkout-queues don't randomly ask each other whether they were breast- or formula-fed, vaginally or C-section delivered, premature or term, when they first walked, how they sleep at night, etc. I'm fed up of all the baby-comparing that goes on out there. Having recently given birth doesn't make our babies, OR our general privacy, public property ...