Same Reason anybody else smokes.
Saturday is the Sabbath in Judaism. Orthodox (and some non-orthodox) Jews will not work. Many non-Orthodox Jews will work, but still remember the Sabbath day in their own ways. (And yes, there are some Orthodox Jews that work on Saturdays, but they do not advertise this fact).
In South Africa, like most countries aside from the USA and the UK, the Jewish communities are overwhelmingly Orthodox. Whether or not a person who attends an Orthodox Synagogue is Orthodox in his "non-synagogue activities" is purely up to the believer. So, some members of the Orthodox community may not actually be observant Jews and would appear like Reform Jews in the USA. However, they would not call themselves Orthodox, but Jews who happen to belong to an Orthodox synagogue. Actual Orthodox Jews in South Africa would be indistinguishable from Orthodox Jews in the USA.
No.
Yes, non-Orthodox Jews can become Orthodox by becoming more observant. Non-Jews can become Orthodox Jews through Orthodox conversion.
Orthodox Jews are strictly observant. Hassidic Jews are even more strict.
Orthodox and Ultra-Orthodox Jews are strict followers of Jewish law.
Traditional Jews tend to be Orthodox, but some non-Orthodox Jews also hold tightly to traditional practices.
The earlocks worn by some very Orthodox and most Hasidic Jews are called payot in Hebrew and payes in Yiddish. There are many variations in spelling.
Unfortunately, in Israel, only Orthodox Jews get all the special privileges.
They are Jews who keep the Torah.
Haredi Jews are ultra orthodox Jews found around the world.
It depends on which denomination within Judaism you are talking about. Non-Orthodox Jews generally follow the customs and social norms of the society they live in. Orthodox Jews vary. Strict, "ultra-orthodox" Jews have no dating at all. They generally rely on parents or other family to help find potential spouses. Modern Orthodox Jews may date, but it depends on the family and some families will require a chaperon.