Choices of society is a common UNESCO catchphrase meaning the distinct ways in which a nation chooses, more or less formally, to organize its social institutions: politics, economics, religion, education, marriage, and the like. It's a phrase which allows UNESCO to acknowledge and dignify the great differences between the many nations it represents.
Unrestricted gun ownership is a choice of society in the United States.
I suspect that the original form is French, choix de société—I see this phrase all over French political discourse. That's the sort of thing that is very difficult to translate into English.
"social choices" would be understood by default as individuals' choices with respect to their own societies and thus fails to capture the nuance that what is meant is the choices made by an entire society.
"a society's choices" does capture that nuance, but it falters when, as in the present instance, you have to speak of the different choices made by multiple societies: "societies' choices" suggests the kinds of choices which each society is constrained to make.
Consequently, UNESCO and its translators have elected to represent the French phrase in English with a calque, a word-for-word translation. You might think of it as a fixed phrase: choices-of-society, bearing a single signification. Within UNESCO, the collocation is familiar and transparent. But for readers outside the organization it is opaque; and its use leads to syntactically awkward constructions like that in your example, where English would ordinarily paraphrase.
The long noun phrase you boldface may be paraphrased something like this
All persons have the right to use their free time for leisure pursuits or travel, provided that in the course of those activities they respect the choices-of-society which all peoples [that is, every nation] are entitled to make for themselves.