I do understand why the OP felt offended, patronised and infantilised. As a younger woman I'd have probably responded in a not dissimilar way. These days I'd only rise to the bait if it was that, bait, an attempt to get a rise out of someone who is clearly an ageing feminist. (I have short hair and big earrings, always a give away). If it's some harmless, friendly chap I meet out walking my dogs, at Church, in the supermarket etc I'll respond in the friendly manner expected and avoid pointing out that calling a women who is almost 70 a girl is not necessarily what she'd want.
However, the majority of posts here say they wouldn't mind, some would actually like it. Ok, live and let live as we've been discussing on the politics thread (lol)