Because if you work for a company here in SA, it almost always comes with a compulsory Retirement Fund option. One of the best savings vehicles we have here.
If you have extra money, you can of course invest it how you wish.
I take it you are not working yet?
You seem to be doing a weird mish-mash of things.
Ignoring most of the above, normally, if you work for a company in SA, they require you to belong to some sort of Retirement Fund. The companies do not run this fund.
Why so hysterical? I made a logical observation as to what you used to make a statement. It seems you couldn't answer logically. And now you are just attempting to make me respond in kind as to your personal attack. Keep On Topic, please.