That's what I was thinking of too - such as the ... individual who presided over the funeral of a family friend a few years ago, shook hands with all the men present and refused to shake the hand of the grieving widow.
Hopefully he spoke respectfully to her instead?
I have met one ultra orthodox rabbi who I was warned wouldn't shake hands, but he did talk to me politely and got his young daughter to take me under her wing, while I was at the synagogue.
I've shaken hands with a conservative Rabbi.
I usually wait until a hand is offered and if not just acknowledge them politely.
You can find yourself treated differently because you are a women at biking events ( as in MC clubs).
Some bikers shake hands with women, others ignore women altogether.
I tend to nod politely at both events
Some women do get upset about it, but life is too short IMO.