I realize that Putin’s biggest fan may not get this, but for some of the younger folks on this thread with remaining mental flexibility let me expand on mas’ comments.
Whether we like it or not, we are continuously measured and judged by the way we comport ourselves, and this includes the degree to which we follow group norms. If one wants to fit into a particular group, it is necessary to understand and adopt some or all of their accepted norms. By not doing so, you are immediately recognized as an outsider. That may never matter to you, in which case pay no heed.
Many opportunities in life, like it or not, exist within or under the control of a particular group. If you want those opportunities, you need to bend to the ways of that group to some degree. This could be something as simple as social acceptance, or it might be access to particular business opportunities, as examples.
An easy way to be marked as a tourist abroad, for example, is to dress exactly as you would back home. There’s no shame in being recognized as a tourist, so don’t get me wrong about where I’m coming from. But if you’d prefer to fly under the radar like a local, it doesn’t take much. We’ve lived in Europe before, and our wardrobes fit in, and we attempt to use whatever words we can of the local language, so we are usually treated like locals, at least at first (until the language difference becomes more obvious), which makes every interaction easier.
as far as knowing a place setting for Buckingham palace, you just never know when that might come in handy. While I am just a typical professional of some sort, I married up and my partner has had roles where we’ve interacted with people way outside my sphere. We’ve dined and otherwise socialized a few times with European and middle eastern royalty, heads of state, ambassadors and cabinet ministers. Having some training in etiquette from my military years, along with decent education, some world experience and command of proper English (plus some decent ability in a second language) came in very handy.
None of that makes me any better than anyone else, but I was able to survive and benefit from those experiences largely because of a few soft skills and mostly useless knowledge picked up along the way.