How could "chaperonage" be the right of a girl?

Question

In "In the Midst of Alarms" (1894) by Robert Barr, Miss Kitty was a rural Canadian carefree girl, Renmark was a professor, and Yates was that young man from New York:

Miss Kitty Bartlett probably would not have denied that she had a sincere liking for the conceited young man from New York. Renmark fell into the error of thinking Miss Kitty a frivolous young person, whereas she was merely a girl who had an inexhaustible fund of high spirits, and one who took a most deplorable pleasure in shocking a serious man. Even Yates made a slight mistake regarding her on one occasion, when they were having an evening walk together, with that freedom from chaperonage which is the birthright of every American girl, whether she belongs to a farmhouse or to the palace of a millionaire.

1. I found that chaperonage was somehow a restrict on girls, so how could it be a birthright of them, or did the author mean a birthright of their families, or it was "that freedom" which is their birthright?

2. Does "shocking a serious man" mean "provoking him"?

Answer 1

American girls were, indeed, much less chaperoned than their European counterparts and regarded this as their right. This would give them freedoms, such as going for a walk with a gentleman, or going on a row boat out on a lake, without a third party hanging about watching.

"Shocking" does not necessarily mean "provoking" though overlap is possible; it merely requires surprise.

Answer 2

It's the New World and the 20^th Century is less than a decade away. North American girls now felt it was acceptable to not be chaperoned all the time. By saying "birthright", the author is expressing this idea in an exaggerated way.

In a similar vein, girls now thought they could say things that would be considered forward or even risqué by a gentleman of the times. In this case, the girl was amused by the reaction of the gentleman, and likely continued the practice simply for that effect.