English Kings are gimped rich figureheads, with maybe some off-the-record, behind-the-scenes influencing. It is an English tradition to subvert power provided the base has sufficient resources and skill to do so, at great sacrifice. While it's not entirely impossible for Charles to order a hit, he can't do things like Putin can.
The Royals will probably hate their life but love the free property and money. I mean, Charles was also a "landlord" over his private lands.
The thing about U.S is that it was the elites want to do things their way differently than the elites of Britain and it is still a system of "elites" that rule the show, with the state Judiciary being the true enforcer of the laws(of course....since lawyers will protect their comrades in the industry) for the general public. There are elites of money(that pay lobbyists) and elites of knowledge(attorneys, and the politician is frequent a former attorney and judges are former attorneys), and it is the latter who are not appreciate for how scummy yet "reasoned" they are.
Because the judiciary is the primary enforcer of laws, many laws "do not apply" to those who do not:
1. Know how to battle well in that sphere
2. Don't have the resources
3. Lack of knowledge the exists(this is both good and bad, because if everyone knew all the "exploits", it's fair enough to say society probably would cannibalize itself)
4. Lack of time to read the giant mound of cases, which includes going back to England because English law is still applicable in many aspects of American common law.
5. The cost structure does not justify enforcement
The thing about the "English way" of petitioning, protest, etc, is that not every place is English in legal history. So, little naive people in general, regardless if they're politicians or laypeople, in non-English locales doing things the "English way" usually wind up dead, jailed, or neutralized. Basically, don't bring tea or fish and chips to a vodka party.