A truly sexist race then?
I vaguely remember this all coming about, the high heel races, walks for charity - in heels, and what could have been more.
What I can't quite remember was the name of the "banner" principle that the charity races were done under. I'm thinking "Pink" something, but that doesn't ring true. What I do (vaguely) remember, was the American version of these charitable enterprises, supported (in principle) those with or who had suffered, breast cancer. The same "banner" title in the UK, was and maybe still is, associated with women who had been abused by men. While this is still a very laudable cause, it's not one many people are happy to be aware of. Put another way, it's a bit of a 'hard sell' as charitable causes go (it seems to me). I wouldn't be surprised to find it's the reason why high-heeled races in the UK almost certainly never happened. I know sponsored walks did, but I don't recall (if they were mentioned) the charity/charities involved.
But women only high heeled races, for prizes? In another era, that's the sort of thing Paul Raymond or Hugh Hefner would have dreamt up.