My mothers parents moved to the US from Scotland in 1923. I was raised to have a viewpoint that the "Royals" were no better or different from you and I and that we were all equal in the USA. That attitude apparantly was one of the reasons my grandparents left Scotland, and what they had instilled in my mother. I was also taught from an early age that even if a Royal came to the USA, that this was the USA and we would treat them with respect, but there was no need to ever use royal titles.
I later became a hotel manager at one of the finest hotels in the US. It was my job to greet royalty from all over the world. Hard as I tried, I could NEVER utter a royal title. The words would not come out of my mouth.
Luckily, most of the men had military titles, which I have no problem using. The ladies and the rest of the men, I just danced around calling them by name.
I have always felt that that was a trait brought over by my grandparents.