Good. No one should have to bow to anyone.https://twitter.com/guidofawkes/status/877483279921942529 …
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A handshake or polite nod works for me. A sign that both are equal as humans, not revering some hierarchical, anachronistic structure
We are talking about a nod. That's precisely what we're talking about.
I'm done. I'll agree to disagree on much of what you've said. Good luck.
I can only think tradition or servility. The US grew out of class structure a while back. Some Brits revel in it to this day.
It is indeed tradition. Nothing 'servile' about according some respect to the Sovereign.
Would you bow to May, Trump and Putin, or shake their hands?
As none of them are sovereigns, I'd act in whatever manner was culturally appropriate. I would, for example, bow to the Emperor of Japan.
I'm all with you on the subject. Just wanting to point out that you'd bow to tons of ppl in Japan, as bowing is very common there. 
Just to check one is not upstaging the dignitary in question with the brilliance of one's own posterior radiance.... or so I'd imagine.
A bow/curtsy is the traditional sign of respect offered to the Sovereign. Not talking about prostrating oneself. It's basic good manners.
Return question: Why does it matter?It's a polite rule. Doing so doesn't harm my self-respect. If you feel it harms yours, that's the issue.
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