Unam Sanctam. Behold your Americanist principles.
The hypocrisy that you've confronted is actually enshrined into law in many of the European republics that were once monarchies. Consider...
*The French constitution has a clause stipulating that the monarchy cannot be restored even if a majority of the people wanted it to be. As Mayor of Paris in 1993, Jacques Chirac prevented royalists from laying a wreath on the spot where King Louis XVI was executed to mark the bicentennial.
*In Greece in the early 1980s, a group of men who tried to start a royalist organization were arrested and charged with treason.
*German monarchists have been harassed by the "Office for the Protection of the Constitution" which views all advocates of changing the constitution as potential neo-Nazis, essentially making it impossible for anyone with monarchist views to gain influence in German politics.
*The Portugese government has refused to hold a referendum on restoring the monarchy despite substantial public support for doing so.
*In Austria, when right-wing Vice-Chancellor Suzanne Riess-Passer publicly addressed Archduke Otto and Archduchess Regina as "Your Imperial Highnesses" on their golden wedding anniversary, she was reprimanded and furiously denounced by socialists who pointed out that the use of titles is illegal in Austria.
In contrast, in the United Kingdom, open and avowed republicans serve in Parliament, hold Cabinet posts, and are vastly overrepresented in the media. Clearly it is much better to be a republican in a monarchy than to be a monarchist in a republic. As you have pointed out, the democrats do not even live by their own principles.